# Callr — full site content (English) > The main pages of www.callr.com as Markdown, for LLMs. French and Spanish versions exist at /fr/ and /es/. --- # Callr — The voice API your business runs on. Capture, attribute, and convert every inbound call across 220+ countries — on the only API-first voice platform that owns its carrier network. The infrastructure under Bien’Ici, MeilleursAgents, Paruvendu, and 300+ companies. **Handling 2.5 million calls daily for 300+ companies** - **220+** — Countries covered - **2.5M+** — Calls daily - **300+** — Companies ## Build voice and SMS into your product — and turn every conversation into intelligence. *Conversation Intelligence* One API. Voice, SMS, email — across 220+ countries on infrastructure we own. Embed click-to-call, SMS notifications, or AI Voice Agents in days, not quarters. Push every event into your CRM, BI, or analytics stack. - Inbound and outbound voice - SMS, email, and webhooks - Call tracking and AI analytics - Automatic transcripts, summaries, and sentiment - Native CRM, BI, and ad-platform connectors ## From an SMS reminder to a full AI Voice Agent — built once, run everywhere. *Customer experience* Design call flows in low-code. Trigger them on any event in your stack. Branch on caller intent, route to the right agent, escalate to a human when it matters — all running serverless on Callr’s infrastructure. - Build flows in hours, not months — in low-code. - Branch, route, transcribe, summarise. - Plug in any LLM you choose. ## Make every call your sales team takes more profitable. *Sales enablement* Qualify the caller before the rep picks up. Whisper the context as the call connects. Push the AI summary into the CRM the moment the call ends. Less manual logging, fewer dropped follow-ups, more closed deals. - Qualify and enrich callers with AI Agents - Auto-update your CRM after every call - Analyse every interaction with AI - Track team performance, call by call ## What if every phone call was as measurable as a click? *Conversation Intelligence* Callr turns every call into structured data: transcript, AI summary, sentiment, intent, satisfaction — defined in your prompts, not ours. Years of customer signal locked inside conversations, finally available to your product, marketing, and BI teams. - Generate transcripts and recaps in seconds - Extract sentiment, intent, and satisfaction - Auto-enrich your CRM and analytics ## Built to slot into the stack you already run. *Integrations* API-first, low-code-ready, fully serverless. Native connectors for Salesforce, HubSpot, Google Analytics, and Google Ads. A documented REST API with code examples. Webhooks for everything that moves. - API-based - Serverless - Low-code ## Bring your own AI model. - Plug GPT, Claude, Mistral, Llama, or your in-house stack. - Extract insights such as customer sentiment, intent, satisfaction, and more. - Automatically enrich your CRM. Callr works with any self-hosted private and public AI major models: ## You choose the law that governs your data. Callr runs two companies — TCLR SAS in France and The Callr Corp in the United States. When you sign up, you decide which one holds your contract and which law applies: EU law or US law. Most providers force one regime on you; we let you choose — something no competitor offers. - **EU law — TCLR SAS (France)** — Your contract is held by TCLR SAS in France and governed by EU and French law, with full GDPR. Your data stays under European jurisdiction — outside the reach of the US CLOUD Act and FISA 702. - **US law — The Callr Corp (United States)** — Your contract is held by The Callr Corp in the United States and governed by US law — the familiar choice for American businesses that need stateside contracting, billing and compliance. - **Our servers, our data centers**: Callr operates its own hardware in owned and colocated facilities. We don’t rent compute from a hyperscaler, so your data doesn’t sit on infrastructure controlled by a third party. - **Choose your geography**: Pin your numbers and data to France, the United States, or Singapore. One platform, three regions — you decide where data physically lives for residency, latency and compliance. - **Same platform, either way**: The APIs, numbers and features are identical whichever jurisdiction you pick. Your legal choice never costs you product or performance. - **A genuine EU option**: Because Callr owns its French infrastructure through TCLR SAS, the EU-law path is the real thing — your data on Callr-owned servers in France, under EU jurisdiction, not a US provider’s European region. --- # Case studies Property portals, restaurant platforms, and communications providers build on Callr’s voice and SMS API to capture, attribute, and convert every call. Here’s how. ## How Bien’ici streamlines and monetizes property leads with Callr *Bien’ici · Real estate · Property portal* France’s third-largest property portal brands every lead and proves its value to 12,000+ professionals with call tracking on Callr’s voice API. - **15M+** — Monthly visits - **12,000+** — Professionals served - **100,000** — Tracked numbers ### The challenge Real estate is a high-consideration business built on trust, and it plays out across both digital and physical touchpoints. Bien’ici needed to bridge the two — connecting online searchers with agents by phone — while proving to professionals that the leads it delivers are real and valuable. ### The solution Call tracking on Callr’s voice API assigns a dedicated phone number to each listing. Buyers reach the right agent in one tap, and a short branded whisper plays as the call connects, keeping Bien’ici present at the most important moment. To run it at national scale, Bien’ici secured a dedicated block of 100,000 tracked numbers from the French regulator — becoming the first French property portal to offer call tracking. ### The results - First French property portal to offer call tracking - Every inbound lead branded as a Bien’ici lead - Supports 50+ field sales representatives with direct client contact - Attribution metrics that demonstrate the value of each lead - An API the team found easy to integrate, backed by responsive support > “Call tracking is greatly appreciated by our clients. It’s increased awareness of our brand and the trust that our clients have in our services.” — Dassin Bidouzo, Chief Digital Officer at Bien’ici ## Business Lead helps small businesses turn more calls into customers with Callr *Business Lead · Communications technology · Inbound for SMBs* A communications provider that lets local businesses handle every inbound call and SMS — no dedicated team, no third-party call center — built on Callr’s API. - **2013** — Building on Callr since - **1 in 3** — SMB calls go unanswered - **Voice + SMS** — On a single API ### The challenge Around one in three calls to a small business goes unanswered — and every missed call is a missed customer. Yet enterprise-grade contact tools were too complex and too costly for SMEs, leaving a large, underserved market. Business Lead set out to build something simple enough for any local business to adopt, yet reliable enough to handle every inbound interaction across channels. ### The solution Founded in 2013, Business Lead chose Callr’s voice API for programmatic number provisioning and scalable communication workflows. The platform captures every inbound call and inquiry, sets appointments over SMS, and routes calls intelligently using real-time transcription. As demand grew, Business Lead expanded geographically into the Benelux region and the French overseas territories — confident the underlying infrastructure would scale with it. ### The results - More calls captured — and more calls monetized - Big-business customer care without the headcount or call-center overhead - Scalability, reliability, and coverage across every customer segment - A relationship of trust and long-term confidence in Callr’s roadmap > “We have worked with Callr since the beginning and our businesses have grown together. We appreciate their responsiveness and their ability to continue evolving their API.” — Yannick Fauchille, Co-founder of Business Lead ## Zenchef proves its value to restaurants with call tracking *Zenchef · Restaurant SaaS · Marketing platform* The restaurant marketing platform uses unique tracked numbers and SMS on Callr’s API to prove — in hard numbers — the bookings it drives for 3,000+ restaurants. - **3,000+** — Restaurants worldwide - **15,500** — Inbound calls / week - **7,600** — SMS / week ### The challenge Restaurant operators needed proof that Zenchef actually drives business — and call tracking was the most reliable way to show how many inbound calls the platform generates for each restaurant. ### The solution Zenchef uses the Callr API to generate a unique phone number for each restaurant, deployed across its website, online ads, and social media. Every inbound call is then precisely attributed to the channel that produced it. A short call whisper plays before each call connects, reinforcing where the lead came from. The same API powers Zenchef’s SMS — booking confirmations, review requests, and payment collection — after the team had struggled with two other providers. ### The results - Around 2,000 tracked numbers managed every week - 15,500 inbound calls and 7,600 SMS handled weekly - Clear proof of the bookings Zenchef drives for each restaurant - Automated payment collection and smoother reservation management > “We tried two other SMS solutions before Callr, but the APIs were complex to integrate and there were lots of technical glitches. Callr’s API is clear, and integration was quick and easy.” — Julien Balmont, Co-founder & CTO of Zenchef --- # Legal Notices *Last updated: 24 June 2026* ## Site publisher This website is published by: - **Company:** TCLR - **Legal form:** Société par actions simplifiée (SAS) under French law - **Registered office:** 128 rue La Boétie, 75008 Paris, France - **Share capital:** 113 000,00 € - **Trade register (RCS):** Paris 528 684 079 - **VAT number:** FR11528684079 - **Contact email:** dpo@callr.com - **Publication director:** Taoufik ZAGDOUD ## Hosting This website is hosted on Cloudflare Pages — Cloudflare, Inc., 101 Townsend Street, San Francisco, CA 94107, USA — https://www.cloudflare.com. ## Intellectual property All content published on this site (text, images, videos, trademarks, logos, designs, source code) is the exclusive property of TCLR or its partners. Any reproduction, distribution or use, even partial, without prior written authorisation is strictly prohibited. ## Personal data protection In accordance with the EU General Data Protection Regulation (GDPR): Purpose: management of customer accounts, communications, and the recording and analysis of calls. Data collected: identity, technical logs, call content, metadata. Retention period: logs and CDRs are kept for 3 years; audio recordings and transcriptions according to the customer’s settings. Your rights: access, rectification, erasure, objection, portability, and withdrawal of consent. To exercise your rights, contact dpo@callr.com. ## Cookies and trackers The site uses essential technical cookies and, with your consent, analytics cookies. You can manage your cookie preferences via the cookie banner or your browser settings. ## Liability TCLR strives to ensure the accuracy and regular updating of the information published on this site. However, no guarantee is given as to the completeness or reliability of the content. Use of the site is at the user’s own risk. ## Governing law and jurisdiction These legal notices are governed by French law. Any dispute shall fall under the exclusive jurisdiction of the courts of Paris, France, unless otherwise required by law. --- # Privacy Policy *Effective date: 14 November 2024* At Callr, we are committed to protecting your privacy. This policy outlines how we collect, use, and safeguard your personal data in compliance with the General Data Protection Regulation (GDPR). ## Data controller and your choice of law Callr is operated by two companies: TCLR SAS in France and The Callr Corp in the United States. When you create your account, you choose which entity contracts with you — and, with it, the law that governs your personal data. **If you choose EU law:** - TCLR SAS (France) is your data controller. - Your personal data is processed under EU and French law and the GDPR. - Your data is hosted on Callr-owned servers in France (see Section 5). **If you choose US law:** - The Callr Corp (United States) is your data controller. - Your personal data is processed under applicable United States law. > The sections below detail Callr’s data practices. Where they reference France, the EU or the GDPR, they describe the EU-law option; equivalent terms under United States law apply to the US-law option. ## 1. Data we collect **Customer information:** - Company name and legal name - First name and last name - Email address - Phone number - Billing information - Technical contacts - Billing contacts - Company registration documents or any other submitted legal documents **Call Data Records (CDRs):** - Calling number - Caller ID (number displayed) - Number dialed - Start time of the call - Call duration CDRs are detailed records of telecommunication transactions used for billing and analysis. **Call recordings:** - Voice recordings of calls (caller, callee, or both, as chosen by you) - Transcriptions of recordings processed via Microsoft Azure (Western Europe only) > Voice recordings are stored on our servers in France. You can delete these recordings at any time and store them on your own servers. ## 2. How we use your data - Service provision: to provide and maintain our telecommunication services. - Billing: for processing payments and billing purposes. - Dispute resolution: to address and resolve any disputes or issues. - Legal compliance: to comply with legal obligations and law enforcement requests. - Customer support: to communicate with you and provide support. We store CDRs for 3 years for billing, dispute resolution, and legal compliance purposes. ## 3. Your data rights Under the GDPR, you have the right to: - Access: request access to your personal data. - Rectification: request correction of inaccurate data. - Erasure: request deletion of your data, subject to legal obligations. - Restriction: request restriction of processing your data. - Portability: receive your data in a structured, commonly used format. - Objection: object to the processing of your data. - Withdraw consent: withdraw consent at any time where processing is based on consent. ## 4. Exercising your rights To exercise your rights, please contact us at: - Email: dpo@callr.com - Address: TCLR SAS, 128 rue La Boétie, 75008 Paris, France We will respond to your request in accordance with GDPR timeframes. ## 5. Data security We implement appropriate technical and organisational measures to protect your data against unauthorised access, alteration, disclosure, or destruction. All data is stored securely on our servers located in France, and any transcriptions are processed in Western Europe. **Server locations:** - EQUINIX (PA2): 114 rue Ambroise Croizat, 93200 Saint-Denis, France - TELEHOUSE (TH2): 137 boulevard Voltaire, 75011 Paris, France ## 6. Contact us If you have any questions about this privacy policy or our data practices, please contact us at: - Email: dpo@callr.com - Address: TCLR SAS, 128 rue La Boétie, 75008 Paris, France Thank you for trusting Callr with your communication needs. We are dedicated to safeguarding your privacy and data. --- # Callr vs Kaisa (Freespee) 2026: Call Tracking & Conversation Intelligence for Marketplaces *2026-06-09 · Callr* Compare Callr and Kaisa (Freespee) for marketplace call tracking and conversation intelligence: carrier-owned infrastructure vs. a wholesale-carrier software layer. If phone calls are the moment your marketplace earns revenue, the platform behind your call tracking is a strategic decision, not a procurement detail. This guide compares Callr and Kaisa — the platform formerly known as Freespee — for marketplaces that bill advertisers on phone leads and need conversation intelligence to prove those leads are worth paying for. ## Overview Kaisa, previously Freespee, has offered call tracking to automotive dealerships and real estate portals since 2009. Founded in Uppsala, Sweden, it built its name connecting advertising spend to phone conversations for brands such as Toyota, Suzuki, JLL, and eBay. In January 2026, the Swedish private equity firm Monterro acquired Kaisa, a sign of continued investment in the business. For marketplace CTOs and product leaders, the decision comes down to architecture: do you want call tracking and conversation intelligence running on a telecom carrier you control, or on a software layer that buys its telephony from a wholesale carrier? The rest of this comparison works through that question. ## Why call tracking matters for marketplaces In marketplace models where the phone call is the revenue event, call tracking is the proof layer between your platform and the advertisers paying you. When a real estate portal charges agents per lead, or an automotive marketplace bills dealers per qualified inquiry, you need data that shows the calls actually happened. That is why conversation intelligence is inseparable from call tracking. Tracking on its own confirms a call took place; it does not tell you whether the call was worth anything. Transcription, intent detection, sentiment scoring, and keyword analysis let you show advertisers that calls were qualified leads — which is what justifies premium fees and keeps advertisers renewing. ## Call tracking: carrier-grade attribution vs. wholesale-dependent tracking Both platforms cover the fundamentals: dynamic number insertion, source attribution, call recording, and analytics. The differences show up at scale. ### Kaisa's architecture According to its public materials, Kaisa provisions numbers and routes calls through BICS, the Belgian wholesale carrier. Call tracking data travels from BICS infrastructure through Kaisa's software layer and into its analytics dashboards. Because routing and reporting live in two separate systems, attribution data has to be reconciled between them, which can introduce latency and discrepancies at high volume. ### Callr's architecture Callr is a registered telecom carrier. Call tracking runs on the same infrastructure that carries the call — from the session border controller, through the media server, to the analytics engine. There is one system, not two. What that means for a marketplace: - **Zero-discrepancy attribution.** The system that routes the call is the system that attributes it, so there is nothing to reconcile. - **Real-time reporting.** Call events fire from the carrier layer itself, without waiting on a sync between platforms. - **Number provisioning at carrier speed.** Numbers come from owned inventory across 220+ countries, with same-day activation. - **Scale capacity.** Callr handles 2.5 million calls per day on its own infrastructure, without negotiating capacity upstream. ## Conversation intelligence: the marketplace monetization engine Call tracking confirms that a call happened. Conversation intelligence tells you what it was worth. For a marketplace, that capability supports: - Automated lead qualification across high call volumes - Advertiser ROI proof through qualified-lead counts and buying signals - Quality control across your agent and dealer networks - Dynamic pricing inputs based on call intent data ### Kaisa's approach Kaisa offers AI-assisted features including keyword spotting and call summarization. Monterro's acquisition reportedly includes plans to expand AI development, though the specifics of production-ready conversation intelligence are limited in Kaisa's public documentation. ### Callr's approach Callr's conversation intelligence is native to the carrier platform: it processes media streams on the same infrastructure that handles the call. - **Real-time transcription.** Every call is transcribed on carrier infrastructure, with lead-quality data available within seconds of the call ending. - **Intent detection and scoring.** AI models identify marketplace buying signals and assign qualification scores. - **Sentiment analysis.** Track caller satisfaction across your marketplace networks. - **Custom keyword libraries.** Configure vertical-specific vocabulary — for real estate, terms like viewing, mortgage, and offer; for automotive, test drive, financing, and trade-in. - **PII redaction.** Personal information is redacted automatically to support GDPR compliance. - **Call summarization.** Every conversation gets an AI-generated summary. ## Real estate vertical analysis Real estate is a high-value, low-frequency market. A single qualified call can represent more than €10,000 in commission revenue for an agent — and hundreds of euros in platform fees. Accuracy matters because each call carries so much weight. Several real estate platforms run their call tracking and conversation intelligence on Callr, including CoStar Group, Bien'Ici, MeilleursAgents, and RealAdvisor. Typical real estate marketplace requirements include: - Listing-level attribution with 50,000+ numbers provisioned - Geographic number matching across 220+ countries from carrier inventory - Whisper messages that give the agent listing context before the call connects - Missed-call recovery through automated callbacks and SMS - Conversation qualification that separates inquiry-stage calls from conversion-stage calls ## Automotive vertical analysis Automotive is Kaisa's strongest vertical, with clients including Toyota, Suzuki, and major dealer groups. Automotive marketplace requirements typically include: - Dealer-level call tracking with 5,000+ tracking numbers and per-dealer dashboards - Lead scoring that turns call volume into qualified pipeline metrics - Call-handling quality monitoring powered by conversation intelligence - Multi-location routing built with Callr Actions on carrier infrastructure - After-hours AI qualification and callback scheduling Kaisa holds the incumbent advantage in automotive. Callr's strength is infrastructure depth: carrier-grade quality across 220+ countries, conversation intelligence built into the platform, and Callr Actions for programmable call handling. ## Callr Actions: programmable voice scenarios This is a capability category Kaisa does not offer. In Callr Actions you author a scenario that orchestrates your call flow end to end: - **Intelligent call routing.** Route by listing type, caller location, time of day, or agent availability. - **AI-powered qualification.** Pre-qualify callers with a voice AI agent before connecting them to an advertiser. - **Automated follow-up.** Chain missed call → SMS → callback scheduling → agent notification in a single scenario. - **IVR for multi-listing portfolios.** Built in YAML and updated through the API as your listings change. ## Where Kaisa wins - Multi-channel engagement orchestration across voice, messaging, web chat, and digital ad touchpoints - Incumbency in automotive dealer networks, with established workflows and domain expertise - Monterro PE backing, which provides stability and a committed roadmap - Breadth of buyer-journey attribution across digital-to-physical touchpoints ## Where Callr wins - **Call tracking depth.** Carrier-native attribution with no reconciliation step. - **Conversation intelligence built in.** Transcription, intent detection, sentiment, scoring, and PII redaction are native to the platform. - **Marketplace scale proof.** CoStar, Bien'Ici, MeilleursAgents, and RealAdvisor deployments. - **Callr Actions.** Programmable voice scenarios with no Kaisa equivalent. - **220+ country coverage**, compared with roughly 120 via BICS. - **EU compliance simplicity.** One data processor means simpler DPAs and audits. - **Carrier economics.** No wholesale margin stacked on top of your telephony. - **Infrastructure capacity.** 2.5 million calls per day on owned infrastructure. ## Decision framework Choose Kaisa if your primary need is multi-channel engagement orchestration and you operate within roughly 120 countries. Choose Callr if phone calls are your marketplace's revenue event — if call tracking accuracy determines how you bill advertisers, conversation intelligence proves lead quality, and you need programmable voice scenarios across 220+ countries on infrastructure you control. --- # Callr vs iovox 2026: Call Tracking & Conversation Intelligence for Marketplaces *2026-06-09 · Callr* Compare Callr and iovox for marketplace call tracking: carrier-native attribution, built-in conversation intelligence, voice AI flows, EU residency and pricing. If phone calls are how your marketplace makes money, the platform you use to track them is part of your billing system, not just your marketing stack. This guide compares Callr and iovox so you can choose the right foundation for call tracking and conversation intelligence across real estate, automotive, and classifieds platforms. ## Introduction iovox has worked in call tracking since 2006 and is well established as a white-label tracking provider, with offices in London, Paris, and San Francisco. Its platform focuses on marketplaces, classifieds, and directories: it assigns tracking numbers to listings and measures the calls those listings generate. The key architectural difference is that iovox operates as a software layer on top of third-party carriers, whereas Callr is itself a registered telecom carrier. This guide is written for product, engineering, and marketing leaders at marketplace platforms, real estate portals, automotive classifieds, and multi-sided platforms, where call tracking is the proof layer behind monetization and conversation intelligence keeps advertisers renewing. ## Call Tracking for Marketplaces: Why Architecture Matters In a marketplace model, call tracking behaves more like billing infrastructure than marketing attribution. That makes the architecture of your tracking platform a business-critical decision rather than a tooling preference. **iovox's architecture:** a software application that provisions numbers and routes calls through upstream carrier partners, with coverage in 60+ countries. The call tracking logic runs in iovox's software layer, and conversation intelligence (iovox Insights) is offered as a separate product tier. **Callr's architecture:** Callr is a registered telecom carrier with direct fiber interconnections to 50+ Tier 1 and Tier 2 operators worldwide. Call tracking, conversation intelligence, and voice AI all run on the same carrier infrastructure that physically carries the call, so there are no handoffs between separate systems. ## Call Tracking Depth: Same Features, Different Execution Both platforms offer dynamic number insertion, source attribution, call recording, and analytics dashboards. Where they diverge is in how those features are executed. ### Where iovox Delivers Well - **WebConnect:** iovox's JavaScript widget turns elements on a webpage into click-to-call buttons with attribution, and it is widely deployed across classifieds and directory sites. - **White-label heritage:** iovox built its platform around white-label use from the start, which gives it two decades of purpose-built white-label tooling. - **Dedicated listing numbers:** iovox has spent more than 20 years refining the practice of assigning a unique number to each classified listing. ### Where Callr's Carrier-Native Architecture Goes Deeper - **Zero-discrepancy attribution:** because the system that routes the call also attributes it, there is no reconciliation needed between carrier CDRs and software-layer logs. - **Real-time call events:** attribution data fires from the carrier layer the moment a call connects. - **Provisioning at carrier scale:** Callr provisions numbers from its own inventory across 220+ countries, which supports same-day activation when you onboard listings in bulk. - **Call quality as tracking quality:** quality issues can be diagnosed at the SIP signaling level, on infrastructure Callr owns. ## Conversation Intelligence: Add-On Tier vs. Built-In Engine ### iovox Insights iovox provides conversation intelligence through its Insights product tier, which includes transcription, keyword spotting, sentiment analysis, call summaries, PII redaction, and intent recognition. Insights sits on top of the call tracking platform, which in turn depends on upstream carrier infrastructure. ### Callr's Built-In Conversation Intelligence Running on the same carrier infrastructure that handles the media stream, Callr includes: - **Real-time transcription:** every call is transcribed on carrier infrastructure as it happens, and lead quality scores appear within seconds of the call ending. - **Intent detection for marketplace conversations:** AI models pick up vertical-specific buying signals across real estate, automotive, and classifieds. - **Sentiment analysis:** track caller satisfaction and agent quality across your marketplace network. - **Custom keyword libraries:** configure industry-specific terminology for real estate, automotive, and classifieds. - **PII redaction:** personal information is automatically removed from transcripts to support GDPR compliance. - **Call scoring:** every conversation gets a composite score you can use to qualify advertiser leads. ## Real Estate Marketplaces: The Call Tracking Monetization Model Real estate marketplaces live and die by attribution accuracy, especially when you charge agents €50–€200 per qualified lead. Marketplaces such as CoStar Group, Bien'Ici, MeilleursAgents, and RealAdvisor process hundreds of thousands of calls each month on Callr and use conversation intelligence to prove ROI to their advertisers. ### What Real Estate Marketplaces Need - **Listing-level attribution:** Callr provisions 50,000+ numbers from carrier inventory; iovox operates across 60+ countries. - **Lead qualification by conversation content:** Callr's built-in conversation intelligence scores calls automatically, where iovox requires its Insights upgrade. - **Geographic number matching:** Callr provides local numbers across 220+ countries, compared with iovox's 60+. - **Advertiser reporting with proof:** Callr returns tracking data and conversation intelligence in a single API response. - **Missed call recovery:** Callr Actions automates the full missed-call workflow; iovox does not offer programmable voice flow automation. ## Automotive Marketplaces: Qualifying Dealer Leads at Scale Automotive advertisers expect proof of call quality. A dealer paying €5,000/month needs the calls to be genuinely qualified, or they churn. ### Key Requirements - **Dealer-level tracking with qualification:** each call is both tracked and scored inside one platform. - **Call handling quality monitoring:** Callr's conversation intelligence surfaces patterns across thousands of dealers automatically. - **Multi-location intelligent routing:** Callr Actions routes calls by proximity, inventory, and availability. - **After-hours qualification:** Callr's voice AI agent greets callers, qualifies intent, captures their preferences, and schedules callbacks. - **Pan-European coverage:** Callr's 220+ countries, compared with iovox's 60+. ## Callr Actions: Voice AI Flows for Marketplaces This is a capability category that iovox does not address. In Callr Actions you build a scenario that can: - **Qualify with AI before connection:** Callr assesses intent before routing, sending high-intent callers to advertisers and low-intent callers to voicemail. - **Route by marketplace context:** route by listing type, price range, caller history, advertiser capacity, and time of day. - **Recover missed calls automatically:** a missed call can trigger an SMS with the listing link, a callback offer, and an agent notification. - **Enforce marketplace quality:** conversation intelligence can trigger platform interventions when poor call handling is detected. ## EU Compliance and Data Residency Callr is headquartered in Paris, is a registered EU telecom carrier, and processes call data in EU data centers by default. Because Callr owns the carrier infrastructure, there is a single data processor in the DPA chain, which keeps your GDPR structure simpler. iovox has offices in London and Paris, and its data processing involves iovox together with its upstream carrier partners, meaning multiple parties sit in the voice data chain. For platforms storing millions of call recordings and transcripts, the difference between one processor and several is material during an audit. ## Pricing: Total Cost for Marketplace Operations **iovox:** according to publicly listed pricing, a Starter plan (basic), Professional at $500/month, and Enterprise starting at $2,000/month. Conversation intelligence (Insights) is priced separately, and total cost often exceeds $2,500/month. **Callr Professional:** €599/month, which includes call tracking, conversation intelligence, Callr Actions, and API access. There is no separate tier for conversation intelligence. ## Where iovox Wins - **White-label heritage:** 20 years of white-label-specific tooling, purpose-built for platforms that need invisible branding. - **WebConnect simplicity:** a click-to-call widget proven across two decades of classifieds deployment. - **Starter tier accessibility:** an easy entry point for small platforms testing call tracking. - **Classifieds expertise:** deeply refined listing-level tracking patterns. ## Where Callr Wins - **Call tracking on carrier infrastructure:** zero-discrepancy attribution, because the system that routes the call is the system that attributes it. - **Conversation intelligence built in:** transcription, intent detection, sentiment, scoring, and PII redaction are included in the Professional plan. - **Marketplace-proven at scale:** some of Europe's largest real estate marketplaces run on Callr infrastructure. - **Callr Actions:** voice AI flows for qualification, routing, and missed call recovery. - **220+ country coverage:** compared with iovox's 60+, which matters for global platforms. - **EU compliance by default:** a single data processor with EU data residency. - **Carrier economics at scale:** no upstream margin stacking, which gives a real per-minute cost advantage at volume. - **2.5M calls/day capacity:** on owned infrastructure, without upstream constraints. ## The Decision Framework Choose iovox if white-label is your primary requirement, WebConnect's deployment simplicity is essential, your operations stay within 60 countries, and basic attribution without deep conversation intelligence is enough. Choose Callr if phone calls are your marketplace's monetization event, call tracking accuracy determines advertiser billing, conversation intelligence proves lead quality, you need AI-powered voice flows, and your operations span 220+ countries with EU-native compliance requirements. For real estate marketplaces, automotive portals, and classifieds platforms where every call is billable and every conversation carries proof of value, the real question is simple: should call tracking and conversation intelligence run as software layers on someone else's infrastructure, or as carrier-native systems where attribution, intelligence, and execution all share one platform? --- # Callr vs Plivo 2026: Carrier-Native Infrastructure vs. the Aggregator Model *2026-06-09 · Callr* Compare Callr and Plivo in 2026: owned EU carrier infrastructure vs. the aggregator model, voice AI options, compliance, pricing, and migration. Choosing a voice platform comes down to a single architectural question: do you want to own the network carrying your calls, or rent capacity on top of someone else's? Callr and Plivo answer that question differently, and the difference shapes everything from latency and call quality to compliance and total cost. This guide compares the two honestly — including where each one is the better fit. ## Architecture: Owned Infrastructure vs. Purchased Capacity Callr is a registered telecom carrier with direct fiber interconnections to 50+ Tier 1 and Tier 2 operators, and holds carrier licenses across several EU countries. You run on infrastructure Callr owns end to end. Plivo operates as an aggregator: it sources voice capacity from upstream carriers and exposes it through an API layer. The company was founded in India and is now headquartered in the US. Owning the network gives you four concrete advantages: - **Latency control** — Direct interconnections remove intermediate hops. For voice AI, where every millisecond of delay is audible in the conversation, that control matters. - **Quality of service** — End-to-end ownership lets Callr enforce QoS across the whole path. An aggregator inherits whatever quality its upstream providers deliver. - **Number provisioning** — Callr provisions numbers directly from its own inventory across 220+ countries, without depending on third-party brokers. - **Troubleshooting depth** — Carrier-level access lets Callr trace a problem down to the signaling layer. An aggregator's visibility stops at its upstream provider's API. ## Voice AI: Two Different Philosophies ### Plivo's Vibe Agent Plivo's no-code AI agent builder targets sub-500ms latency and supports voice, SMS, WhatsApp, and chat. According to its documentation, it orchestrates third-party components — Deepgram for speech-to-text, OpenAI for the language model, and ElevenLabs for text-to-speech — and follows a pay-as-you-go pricing model. This is a strong fit when you want to prototype quickly without wiring up several vendor integrations yourself. ### Callr Actions Callr Actions is a low-code product for building voice scenarios — including AI agent conversations — that run serverless on Callr's own infrastructure. Instead of chaining external AI providers behind an integration layer, you author a declarative scenario and execute it with carrier-native guarantees. Here is how the two approaches trade off: - **Component dependency** — Vibe Agent depends on three external providers, so a degradation in any one can affect the whole conversation. Running on Callr reduces the number of external dependency points. - **Customization** — A scenario in Callr Actions is version-controllable and testable logic. No-code builders optimize for speed to a demo rather than for handling production complexity. - **Infrastructure proximity** — A Callr Actions scenario executes on the same carrier infrastructure that handles the media stream, which removes network hops. - **Roadmap exposure** — With Vibe Agent, you are indirectly tied to the roadmaps and pricing of Deepgram, OpenAI, and ElevenLabs through Plivo's integration layer. ## EU Compliance and Data Residency Callr's real compliance advantage is structural: it is a registered carrier in multiple EU jurisdictions, headquartered in Paris, running on infrastructure it owns. Call data, recordings, and metadata reside in EU data centers by default. GDPR alignment reflects the regulatory environment Callr was built in, rather than a feature added after the fact. For European operations, owned EU infrastructure and default EU residency answer questions that an aggregator outside the EU has to work harder to address: - **Data residency** — Where do your recordings and transcripts physically live, and under which jurisdiction? With Callr the answer is the EU, by default. - **Cross-border transfers** — Voice data frequently contains personally identifiable information. Keeping it on EU infrastructure avoids the additional safeguards — Data Processing Agreements and Standard Contractual Clauses — that transfers to non-EU processors typically require. - **Telecom accountability** — As an EU carrier, Callr operates under national regulatory oversight, which provides a clear line of legal accountability for the network itself. - **EU AI Act readiness** — As enforcement ramps up, voice AI systems that process EU data face transparency and risk-classification obligations. EU-based infrastructure makes meeting them simpler. ## Integrated Platform vs. Point Solution Plivo keeps a focused scope: a voice API, an SMS API, and Vibe Agent for conversational AI. Callr bundles capabilities that would otherwise require several vendors: - **Call tracking** — Dynamic number insertion, source attribution, and campaign-level analytics, native to the platform. - **Conversation intelligence** — Transcription, keyword detection, sentiment analysis, and call scoring, built into the call-handling layer. - **Voice AI via Callr Actions** — Serverless voice scenarios, including AI agent conversations, executing on carrier infrastructure. - **Global number inventory** — 220+ countries provisioned directly from Callr's carrier relationships. If you currently run Plivo alongside separate tools for call tracking, conversation intelligence, and AI agents, Callr consolidates that stack into fewer vendors and fewer integration points. ## Scale and Reliability Callr handles 2.5 million calls a day for 300+ companies, with production voice traffic since 2011. Plivo has also operated at significant scale since 2012, and both platforms handle high-volume workloads. The difference shows up during failures: carrier-level ownership lets Callr resolve issues at layers an aggregator cannot reach. ## Pricing Model Plivo's positioning centers on low per-unit cost. Its pay-as-you-go rates come with minimal commitments, which is appealing for early-stage teams watching every euro. Callr's pricing reflects carrier-grade infrastructure and an integrated feature set: - **Professional plan** — From €599/month, including call tracking, conversation intelligence, and API access. - **Enterprise** — Custom pricing with volume discounts, dedicated support, and carrier-grade SLAs. The two aren't directly comparable. Plivo's per-minute rate looks lower on its own. Once you add a separate call-tracking tool, a conversation-intelligence platform, an AI agent builder, and the engineering time to integrate them, the total cost of ownership shifts meaningfully. ## Where Plivo Wins - **Tight per-unit budgets** — Basic voice and SMS API access at low per-unit cost with minimal volume commitments. - **US-centric deployment** — Strong US coverage and latency for teams without EU compliance requirements. - **Rapid AI prototyping** — Vibe Agent's no-code builder reaches a proof of concept faster than authoring a scenario. - **SMS-heavy workloads** — A mature, well-documented SMS API with clear pricing advantages. ## Where Callr Wins - **European operations** — GDPR-native, EU data residency by default, and registered-carrier status for EU-focused companies. - **Infrastructure ownership requirements** — Regulated industries, financial services, and healthcare, where network ownership is an audit question. - **Integrated voice intelligence** — Call tracking, conversation intelligence, and voice AI on one platform with a unified data model. - **Global number coverage** — 220+ countries from carrier-direct relationships, with provisioning, porting, and compliance handled by Callr as carrier of record. - **Production voice AI at scale** — Thousands of concurrent AI agent conversations where latency and reliability outweigh no-code convenience. - **Call quality guarantees** — Direct operator interconnections remove the quality variability that comes with buying capacity from third parties. ## Migration from Plivo to Callr ### Phase 1: Number Porting (1–2 weeks) As a registered carrier, Callr handles inbound porting using standard procedures. Your existing Plivo numbers port with no downtime, and international numbers across 220+ countries are provisioned in parallel. ### Phase 2: API Integration (1–2 weeks) Callr exposes a REST API and webhooks that follow standard patterns. Core operations — placing calls, sending SMS, and configuring webhooks — map directly from Plivo's structure, and most teams complete the integration in under two weeks. ### Phase 3: Voice Scenario Migration (1–3 weeks) Your Plivo XML (PHLO) logic translates into Callr Actions scenarios. Migrating a Vibe Agent means redefining the conversation as a scenario in Callr Actions — more control, in exchange for engineering involvement rather than no-code configuration. ### Phase 4: Analytics and Intelligence Activation Once your calls flow through Callr, turning on call tracking and conversation intelligence is configuration-only — no extra vendor contracts and no new data pipelines. Callr provides dedicated migration support, including parallel-running periods where both platforms operate at the same time during the transition. ## The Decision Framework **Choose Plivo** for the lowest per-unit cost on basic voice and SMS in the US market, with minimal compliance requirements. **Choose Callr** for carrier-grade infrastructure, EU compliance by default, integrated voice intelligence, and ownership of the network that carries your calls. The platforms serve different segments. Plivo is a cost-efficient API aggregator. Callr is a carrier-native voice platform. The right choice depends on whether cost-per-minute or infrastructure ownership is your primary constraint. For production voice AI serving European customers at scale — where compliance, latency, and reliability are engineering requirements rather than optional extras — the difference between owning your infrastructure and renting it becomes decisive. --- # Callr vs Telnyx 2026: Two Carrier-Native Platforms, Two Philosophies *2026-06-09 · Callr* Callr vs Telnyx in 2026: both own their carrier infrastructure. Compare EU-native data residency, built-in call tracking, voice AI, and pricing models. This is one of the comparisons technical buyers ask for most. Many voice API providers resell upstream carrier capacity. Callr and Telnyx do not — both own and operate their own telecom infrastructure. Both were started by engineers, and both have invested heavily in voice AI. So the choice between them comes down to three real differences: **where each platform comes from** (EU-native versus US-native), **how each is designed** (an integrated voice platform versus a horizontal API toolkit), and **how you build on it** (declarative low-code scenarios versus a no-code AI agent builder). This guide walks through each one so you can match the platform to what you are actually building. ## Infrastructure: both carrier-owned, different origins ### Callr - **Founded:** 2011, Paris. Fifteen years of continuous carrier operations. - **Status:** Registered telecom carrier, ARCEP-licensed in France with equivalent registrations across the EU. - **Interconnection:** Direct interconnection with 50+ Tier 1 and Tier 2 operators worldwide. - **Number inventory:** Coverage in 220+ countries, provisioned on demand via the API. - **Traffic:** 2.5 million calls per day across 300+ enterprise customers. - **Data residency:** EU by default. Processing, storage, and analytics stay within EU borders unless you explicitly configure otherwise. ### Telnyx - **Founded:** 2016, Chicago, incorporated in Delaware. EU operations were added later. - **Status:** Licensed carrier in 30+ markets, running a private IP network with global points of presence. - **Interconnection:** Private, multi-cloud IP network with direct peering, and GPUs colocated with its telephony points of presence. - **AI infrastructure:** GPU deployments across several regions, including a Paris GPU node for EU-local AI inference. - **Recent additions (2026):** Multi-party AI calls, SIP endpoint registration, and expanded voice AI agent capabilities. ### The infrastructure verdict Both platforms genuinely own their infrastructure. The meaningful difference is **heritage and default posture**. Callr was built as a European carrier in 2011 and has operated under EU telecom regulation for fifteen years. Telnyx was built as a US carrier in 2016 and expanded into EU markets afterward. Neither path is inherently better, but they lead to different compliance defaults, different vendor relationships, and different operational instincts. ## Voice AI: Callr Actions vs Telnyx AI Assistants ### Callr Actions - **Approach:** A declarative low-code way to define voice logic. You write a scenario that lays out call flow, branching, AI interactions, and integrations. - **Philosophy:** Code-reviewable, version-controllable, and CI/CD-friendly. Your voice logic lives alongside your application code. - **Built-in analytics:** Every call automatically feeds Callr's conversation intelligence layer. Transcription, sentiment, keyword detection, and call scoring run without extra configuration. - **Call tracking:** Native call tracking with dynamic number insertion, multi-touch attribution, and source-level analytics, all in the same platform. - **Best for:** Engineering teams that want deterministic, auditable voice logic with AI added where it helps. ### Telnyx AI Assistants - **Approach:** A no-code AI agent builder with sub-200ms latency. You configure AI-powered voice agents visually. - **Philosophy:** Stand up autonomous AI agents quickly. Bring your own LLM or use Telnyx-hosted inference, with custom voice cloning available. - **Infrastructure:** GPUs colocated with telephony points of presence keep latency low between AI inference and voice transport. - **Recent capabilities:** Multi-party AI calls (2026), letting AI agents take part in conference-style interactions. - **Best for:** Teams that want to deploy AI voice agents fast with minimal code, favoring autonomy and natural conversation over step-by-step control. ### The AI philosophy difference This is not a question of who has AI — both do. The real question is **how much control you want versus how much autonomy you grant**. A Callr Actions scenario defines exactly what happens at each step, with AI capabilities invoked at specific decision points. Telnyx's AI Assistants give you an autonomous agent that handles the conversation end to end, with less explicit step-by-step control. If your compliance team needs to review every possible call path before launch, a declarative scenario is straightforward to audit. If you want to stand up a conversational AI agent for appointment booking in an afternoon, a no-code builder may get you there faster. Both are legitimate engineering choices. ## The integrated platform: call tracking plus conversation intelligence This is where the two platforms diverge most clearly. Callr is not only a voice API. It is an **integrated voice platform** that combines programmable voice, call tracking, and conversation intelligence in a single product. ### What Callr includes natively - **Call tracking:** Dynamic number insertion, source attribution, and campaign-level analytics. No separate call tracking vendor needed. - **Conversation intelligence:** Automatic transcription, keyword spotting, sentiment analysis, call scoring, and trend detection across all of your call volume. - **Unified data model:** A single call record holds transport metadata, tracking attribution, AI interaction logs, and conversation analytics. One API call returns all of it. - **Vertical templates:** Pre-built scenarios for real estate (lead qualification, listing inquiries), marketplaces (buyer-seller mediation, trust and safety), and hospitality (reservation management, guest services). ### What Telnyx focuses on - **Programmable voice and messaging APIs:** Broad, well-documented, and performant. - **AI inference infrastructure:** GPU-accelerated and low-latency, with voice cloning and multi-party capabilities. - **Networking and storage:** Telnyx reaches beyond telecom into cloud networking, storage, and compute — a broader infrastructure play. - **Horizontal applicability:** Designed to serve any use case across any vertical, without opinionated templates. ### When this matters If you are building a product where calls generate business intelligence — where you need to know _which channel drove a call_, _what the caller's sentiment was_, and _whether the agent followed the script_ — Callr delivers all of it in one platform with one invoice. With Telnyx, you would typically add separate tools for call tracking and conversation intelligence, which adds integration work and data reconciliation overhead. If you are building raw telephony infrastructure — a CPaaS layer inside your own product, a custom contact center, or a telecom application where call tracking is not relevant — Telnyx's pure API approach gives you exactly that, without paying for capabilities you will not use. ## EU compliance: native versus adapted For European buyers, and for any company processing EU citizen data, this distinction has practical weight. ### Callr's EU posture - Paris-headquartered since 2011. GDPR compliance was the default from the regulation's start, not a later retrofit. - All data processing happens within EU borders by default. No configuration, no add-on pricing. - ARCEP-licensed carrier, subject to EU telecom regulation natively. - French legal entity, with data processing agreements under EU law and EU-jurisdiction dispute resolution. - Fifteen years of relationships with EU regulators, carrier partners, and enterprise procurement teams. ### Telnyx's EU posture - Delaware-incorporated and Chicago-headquartered, with EU operations added as a geographic expansion. - Licensed in 30+ markets including EU countries, with a Paris GPU deployment available for EU-local AI inference. - GDPR-compliant, with data processing agreements and EU data residency options. - As a US-incorporated entity, subject to US legal frameworks such as the CLOUD Act. ### Why this matters for procurement Both platforms can satisfy a GDPR checklist. The difference shows up in **procurement risk assessment**. Callr's genuine differentiator is its owned EU carrier infrastructure with EU data residency on by default — there is nothing to switch on and no extra cost. When your DPO reviews vendor risk, a Paris-headquartered, EU-incorporated, ARCEP-licensed carrier presents a different profile than a Delaware-incorporated entity with EU operations. Neither is automatically disqualifying, and many EU enterprises use US-based infrastructure. But if your organization prefers EU-native vendors, or if you operate in a regulated sector such as healthcare, financial services, or government where data residency is non-negotiable, this distinction matters. ## Pricing **Callr** - **Professional:** From €599/month. Includes programmable voice, call tracking, conversation intelligence, and Callr Actions. - **Enterprise:** Custom pricing, with dedicated infrastructure, custom SLAs, premium support, and vertical-specific configurations. - **Model:** Platform fee plus usage. Call tracking and conversation intelligence are part of the platform, not separate line items. **Telnyx** (per its publicly listed pricing) - **Conversational AI:** From $0.06–$0.08 per minute for AI-powered voice interactions. - **Voice API:** Pay-per-use metered pricing for standard voice calls. - **Model:** Pure usage-based, with no platform fee — you pay for what you consume. ### Pricing analysis The two models reflect different value propositions. A per-minute model is attractive when you want to start with minimal commitment and scale linearly. A platform fee makes economic sense once you account for the bundled call tracking and conversation intelligence, capabilities you would otherwise buy from separate vendors. For a team processing 50,000+ minutes a month that also needs call tracking and analytics, Callr's bundled pricing typically lowers total cost of ownership. For a team that needs pure voice transport without analytics, a usage-only model avoids paying for capabilities it will not use. ## Head-to-head comparison | Feature | Callr | Telnyx | |---------|-------|--------| | Carrier ownership | Yes (since 2011) | Yes (since 2016) | | Headquarters | Paris, France | Chicago, USA (Delaware inc.) | | Voice AI | Callr Actions scenarios (deterministic + AI) | No-code AI agent builder (autonomous agents) | | AI latency | Carrier-grade, sub-second | Sub-200ms (GPU-colocated) | | Call tracking | Native, built in | Not included (third-party required) | | Conversation intelligence | Native, built in | Not included (third-party required) | | Number coverage | 220+ countries | 50+ countries (expanding) | | Data residency | EU by default | Configurable (US default) | | Vertical templates | Real estate, marketplaces, hospitality | Horizontal (build your own) | | Voice cloning | Not available | Yes, custom voice cloning | | Multi-party AI | Not available | Yes (2026) | | Broader infra (storage, compute) | No (voice-focused) | Yes (expanding to full cloud) | | GDPR posture | EU-native, 15 years | Compliant, US-incorporated | | Carrier licenses | EU-primary (ARCEP + multi-country) | 30+ markets globally | ## When to choose Callr - **You want call tracking and conversation intelligence on the same platform as your voice API.** If calls drive revenue and you need attribution, sentiment, and scoring without stitching together three vendors, Callr removes that integration work. - **EU-native compliance is a procurement requirement.** Your DPO, legal team, or regulator requires an EU-headquartered, EU-incorporated vendor with EU data residency by default. - **You operate in real estate, marketplaces, or hospitality.** Callr's vertical depth means faster time to value, with pre-built scenarios and domain-specific conversation intelligence. - **Your engineering team values declarative, auditable voice logic.** Callr Actions scenarios fit your CI/CD pipeline, pass code review, and give compliance teams visibility into every call path. - **You value a long operating track record.** Callr has run carrier infrastructure since 2011. In telecom, operational maturity tends to correlate with reliability. ## When to choose Telnyx - **You want autonomous AI voice agents with minimal code.** Telnyx's no-code AI agent builder, with sub-200ms latency and voice cloning, can get pure AI conversation use cases to production quickly. - **You need multi-party AI calls.** If your use case has AI agents joining conference-style calls — interpreting, mediating, assisting — Telnyx offers this capability in 2026. - **You are building raw telephony infrastructure.** If you do not need call tracking or conversation intelligence, a pure API approach avoids paying for bundled capabilities. - **You want a broader infrastructure play.** Telnyx is expanding beyond telecom into compute, storage, and networking. If you want one vendor for voice plus cloud infrastructure, that is the direction they are building toward. - **Pure usage-based pricing is a requirement.** No platform fee and no minimum commitment — you pay per minute and scale linearly. ## Migration guide: moving from Telnyx to Callr If you have weighed both platforms and decided Callr fits your requirements better, here is the path. ### Phase 1: number porting and parallel operation (weeks 1–3) - Start number porting through Callr's porting API. Callr handles the regulatory paperwork across 220+ countries. - Build your Callr Actions scenarios for your existing call flows. If you are moving from Telnyx AI Assistants, map agent logic to deterministic scenario steps with AI decision points. - Run traffic in parallel: keep Telnyx live for existing numbers while new numbers provision on Callr. ### Phase 2: logic migration (weeks 2–4) - **Telnyx TeXML / Call Control to Callr Actions:** Telnyx's TeXML maps conceptually to a Callr Actions scenario. Both are declarative, so the translation is mostly structural. - **Telnyx AI Assistants to Callr Actions plus AI:** This one needs more thought. Autonomous agent logic has to be broken down into explicit decision trees with AI at each branch point. Callr's solutions team provides migration templates for common patterns. - **Webhook endpoints:** Update your webhook URLs. Callr's event schema is documented, and the support team can share Telnyx-to-Callr field mapping guides. ### Phase 3: analytics activation (weeks 3–5) - Configure call tracking: set up dynamic number pools, attribution rules, and source mapping. This is net-new capability, since Telnyx does not offer it natively. - Enable conversation intelligence: turn on transcription, sentiment analysis, and keyword detection, and define scoring rules for your use case. - Connect your BI stack: Callr's analytics API feeds Looker, Tableau, or custom dashboards with unified call, tracking, and intelligence data. ### Phase 4: cutover and validation (weeks 5–6) - Complete number porting and verify that all routes are active on Callr infrastructure. - Decommission Telnyx resources: terminate API credentials and remove webhook configurations. - Validate conversation intelligence accuracy against your baseline metrics. ### Migration support Callr provides dedicated migration engineering support for teams moving from Telnyx. Because the two platforms share so much at the infrastructure level, these migrations are typically among the most straightforward competitive switches. A full production cutover usually takes four to six weeks with zero downtime. ## Final perspective Callr and Telnyx made the same foundational bet: owning carrier infrastructure gives you control over quality, latency, cost, and compliance that no reseller can match. Where the two differ is in what each built on top of that infrastructure. Telnyx is building a broad cloud platform — voice, messaging, AI, compute, storage, and networking — with a horizontal, API-first approach. Callr has built an **integrated voice intelligence platform**: programmable voice, call tracking, and conversation intelligence in a single product, with depth in specific industries. The right choice depends on what you are building. If voice is one component of a larger infrastructure stack, Telnyx's breadth is compelling. If voice calls are a **core revenue driver** — if you need to track where they come from, understand what was said, and improve conversion — Callr's integrated approach removes the multi-vendor complexity that slows teams down. **Request a technical consultation at callr.com.** Our solutions engineers will map your current Telnyx architecture to Callr's platform and give you a migration timeline specific to your use case. --- # Callr vs Twilio 2026: The Carrier-Native Alternative to the Default Choice *2026-06-09 · Callr* Compare Callr and Twilio for voice in 2026: owned EU carrier infrastructure, default EU data residency, voice AI, real pricing at scale, and a migration path. Twilio is the name most teams reach for first when they need a voice API. It is well documented, widely adopted, and quick to get started with. But "first choice" and "best fit" are not always the same thing — especially once your voice traffic grows, your AI requirements get serious, or EU data residency becomes a hard requirement. This guide compares Callr and Twilio across the factors that actually shape a voice deployment: the underlying infrastructure, compliance, voice AI, pricing at scale, developer experience, and what a migration looks like. We have kept the honest "where Twilio wins" calls in too, because the right answer depends on your use case. ## Infrastructure: owned network vs. resold capacity The clearest difference between the two platforms is what sits underneath the API. **Twilio** operates as a communications platform layered on top of wholesale voice capacity it buys from carriers. Its value comes from the developer experience around that capacity: routing logic, SDKs, and tooling. **Callr** is a licensed telecom carrier. We have run our own network since 2011, with direct interconnections to 50+ Tier 1 and Tier 2 operators. Your voice traffic routes across infrastructure we own and operate, rather than through a reseller layer. ### What that means in practice - **Latency:** Direct peering means fewer routing hops between endpoints. - **Quality control:** When something needs debugging, it happens on our own switches and fiber rather than across a third party. - **Cost structure:** The economics differ at scale — per-minute differences add up as volume grows. - **Reliability:** You are not dependent on a third party's capacity allocation. Neither model is universally better. A resold model gives you fast onboarding and breadth; an owned network gives you control over routing, quality, and cost as you scale. ## EU compliance and GDPR For teams in regulated or compliance-sensitive sectors, where your call data lives matters as much as how the API behaves. **Callr** is headquartered in Paris and operates as a registered EU telecom carrier. By default, your call data, recordings, metadata, and analytics reside in EU data centers. That is the starting configuration, not an add-on you have to assemble — EU data residency is built into the platform because the infrastructure itself is European and operated by us. **Twilio** is a US-headquartered provider and offers EU region options for customers who need them. As with any US-based provider, organizations with strict requirements typically evaluate jurisdictional considerations such as potential US Cloud Act exposure as part of their own assessment. The practical Callr advantage for compliance-sensitive teams comes down to owned EU infrastructure with EU data residency by default — a genuinely European path, rather than a region setting layered on top of a non-EU architecture. ## Voice AI integration Both platforms let you build AI-powered voice experiences, but they take different routes to get there. **Twilio** follows an assembly model: you orchestrate third-party speech-to-text, large language model, and text-to-speech providers through the platform. That gives you maximum freedom to swap individual components. **Callr** integrates speech-to-text, natural language processing, and text-to-speech within a single platform, running directly on our carrier infrastructure. You author your voice logic as a scenario in Callr Actions — our low-code voice product — and it executes on the network rather than depending on an external orchestration layer. Callr also includes conversation intelligence out of the box: sentiment analysis, keyword detection, and call scoring, without bolting on a separate analytics tool. The trade-off is the familiar one. Assembly gives you component-level flexibility; an integrated platform gives you fewer moving parts to build, secure, and maintain. ## Pricing at scale Headline rates and real bills are not the same thing — for either provider. **Twilio's published rates** are roughly $0.0085/min inbound and $0.014/min outbound, with around $1.15/month per phone number, according to its public pricing. **Real-world Twilio costs** tend to run higher than the headline numbers once you factor in billing rounding, recording storage, transcription, CNAM lookups, and regulatory surcharges. Teams commonly report effective costs 10–25% above published rates. **Callr's structure** starts at €599/month for the Professional plan, with volume-based enterprise pricing above that. We do not publish flat per-minute rates, because real per-minute cost depends on destination and volume. Teams running high voice volumes typically report 20–40% savings with Callr versus an equivalent Twilio deployment — before accounting for the third-party tools (analytics, conversation intelligence) that Callr replaces. As always, run the numbers against your own traffic profile. At low volume, per-minute differences rarely compound enough to matter; at high volume, they can become a meaningful line item. ## Developer experience This is where Twilio's maturity shows, and it is worth being straight about it. **Twilio's strengths:** comprehensive documentation, SDKs across many languages, a large developer community, and extensive code samples. If broad ecosystem support is a priority, this is a real advantage. **Callr's approach:** you build voice logic visually as scenarios in Callr Actions, and integrate the rest of the platform through a REST API and webhooks. Event delivery is webhook-based, and enterprise accounts get direct engineering support rather than only a community forum. If your team relies heavily on a particular SDK ecosystem, Twilio's breadth is a genuine plus. If you want owned infrastructure and hands-on support, Callr's model fits better. ## When to choose each platform **Choose Callr when:** - High-volume voice traffic and cost at scale are primary concerns. - EU data residency and GDPR compliance are mandatory requirements. - You want voice AI without assembling a multi-vendor stack. - Call tracking and conversation intelligence are core to your product. - You need international number provisioning across specific markets. - Infrastructure ownership and quality control matter more to you than ecosystem breadth. **Choose Twilio when:** - You are early-stage and want the fastest possible time to first call. - You need voice, SMS, video, and email from a single vendor. - A specific SDK or ecosystem integration is required. - Volume is low enough that per-minute pricing differences do not compound. - You want maximum flexibility to swap individual AI/ML components. - Your team is already deeply invested in Twilio Studio workflows. ## Migration path Moving from Twilio to Callr is a staged process designed to avoid downtime. For most deployments it takes 4–8 weeks end to end, with a dedicated migration engineer for enterprise customers. **Phase 1 — Number porting (1–2 weeks):** Port your numbers with parallel routing in place, so there is no service interruption during the move. **Phase 2 — Logic conversion (1–4 weeks):** Convert your TwiML and Studio flows into Callr Actions scenarios. - Simple IVR: a few days. - Complex multi-step flows: 1–2 weeks. - AI-powered conversational flows: 2–4 weeks. **Phase 3 — Integrations (1–2 weeks):** Update your integrations and configure webhooks against the Callr API. **Phase 4 — Validation (1 week):** Run parallel testing and validation before the full cutover. ## The bottom line Twilio is a strong default, particularly for early-stage, multi-channel, SDK-heavy teams that value ecosystem breadth and fast onboarding. Callr is the carrier-native alternative: an owned EU network, EU data residency by default, integrated voice AI through Callr Actions, and pricing that tends to favor you as volume grows. If voice is core to your product and you are scaling — or compliance is non-negotiable — Callr is worth a serious look. --- # Callr vs Vonage 2026: What the Ericsson Acquisition Means for Developers *2026-06-09 · Callr* Compare Callr and Vonage in 2026: owned EU carrier infrastructure vs an Ericsson subsidiary. Architecture, voice AI, pricing, compliance and migration. In July 2022, Ericsson acquired Vonage for $6.2 billion, pitching the deal as a way to pair Ericsson's global network reach with Vonage's developer-first communications APIs. Three years on, the results look mixed. Vonage was named a Leader in the 2026 IDC MarketScape, yet a number of developers have looked elsewhere. This guide is written for engineering leaders and product heads choosing a voice API platform, and it comes down to one question: do you want a corporate subsidiary, or an independent carrier built for developers? ## How the acquisition reshaped Vonage Before Ericsson stepped in, Vonage competed with Twilio as a developer-first challenger. Today it operates as a wholly owned subsidiary inside Ericsson's Global Communications Platform business area. That ownership has changed how the company works: - **The sales motion moved upmarket.** Enterprise deals with multi-month procurement cycles now take priority. Startups and scale-ups report longer onboarding and slower support. - **The release cadence slowed.** Corporate governance, compliance reviews, and cross-team alignment inside Ericsson add steps between an idea and a shipped feature. - **Platform consolidation is still in progress.** Vonage runs legacy Nexmo infrastructure alongside newer Ericsson backend integrations, which adds complexity for developers who need predictable behavior. None of this makes Vonage a worse product. It reflects the reality that Vonage is a different company than the one many teams chose five years ago. ## Infrastructure: owned network vs leased capacity Callr is a registered telecom carrier with direct fiber interconnections to 50+ Tier 1 and Tier 2 operators worldwide. It is not a reseller leasing capacity from someone else. Vonage, even with Ericsson's telecom assets behind it, operates as a capacity reseller in most markets. Ericsson provides backend support, but Vonage voice traffic generally crosses third-party carrier networks before it reaches the endpoint. Each intermediary adds latency, cost, and another point that can fail. What that means in practice: - **Call quality.** Direct interconnection means fewer hops, lower jitter, and consistent audio across 220+ countries. When you own the path, you can control the quality. - **Number provisioning.** Callr provisions numbers in 220+ countries from its own inventory and direct carrier agreements. Vonage covers a comparable footprint, but through aggregator relationships that can slow provisioning. - **Regulatory control.** As a registered carrier, Callr handles telecom compliance directly, without depending on an intermediary to do it. ## Voice AI: two different philosophies Vonage has invested heavily in AI. Its AWS partnership integrates Amazon Nova Sonic for AI voice agents, its ServiceNow integration adds real-time transcription and AI workflows, and it is building MCP server tooling for agentic use cases. Credit where it is due: Vonage is taking AI seriously. Callr takes a different architectural route. Conversation intelligence and call tracking are built into the platform at the carrier layer, rather than bolted on through third-party partnerships. That means: - **Real-time transcription and analytics** run on Callr's own infrastructure, with data staying within EU boundaries by default. - **Callr Actions** — a low-code system for building voice scenarios — lets your team design IVRs, routing logic, and AI-augmented call handling without writing application code. - **No lock-in to a single AI provider.** Vonage's tight AWS coupling means you inherit Amazon's AI roadmap. Callr's architecture stays AI-provider agnostic, so you can bring the model you want. ## EU compliance: built in, not retrofitted Callr is based in Paris, founded in 2011, and has run inside EU data protection frameworks from the start. GDPR is not a feature you switch on; it is the foundation the platform sits on. Vonage is US-headquartered. Ericsson is Swedish, but Vonage's operations, data processing, and primary infrastructure remain US-centric. For European companies, that difference shows up in a few concrete places: - **Data residency.** Callr processes and stores call data in EU data centers by default, on owned infrastructure. With Vonage, equivalent guarantees can require explicit configuration and, in some cases, an enterprise-tier contract. - **Owned EU path.** Because Callr runs its own EU carrier network, your voice data has a genuine European route by default — you do not have to assemble residency from a patchwork of regional settings. - **DPA simplicity.** Callr's Data Processing Agreements reflect EU-native operations, which keeps legal review straightforward. If your legal team cares about where voice data lives, choosing Callr removes an entire category of compliance discussions. ## Developer experience Vonage's documentation is still strong — a legacy of its developer-first years. The API design is mature, its SDKs cover the major languages, and its community forums remain active. That said, developers report that support response times have grown since the acquisition, and the platform's direction increasingly favors enterprise use cases over developer ergonomics. Callr handles 2.5 million calls per day for 300+ companies, and the platform is built for teams that ship quickly: - **Callr Actions.** Define complex call routing, IVR trees, and webhook integrations as low-code voice scenarios, without building an application around them. - **A REST API and webhooks.** Full programmatic control through a REST API with real-time webhooks for teams that want to drive the platform from their own code. - **Human support.** Callr is founder-led, with around 50 employees. You talk to engineers, not a ticket queue, and response times are measured in hours rather than days. ## Where Vonage wins Honesty matters in a comparison like this. Vonage has real strengths: - **Video API.** Vonage's video platform (formerly TokBox/OpenTok) is excellent. Teams that need embedded video alongside voice get it from one provider. Callr is voice-focused. - **Enterprise certifications.** Ericsson's backing gives Vonage SOC 2 Type II, HIPAA, PCI DSS, and FedRAMP certifications that matter for regulated US industries. - **Brand recognition.** When procurement needs a name the CFO already knows, Ericsson and Vonage check that box. - **Unified CPaaS.** Teams that want voice, video, SMS, and messaging from one vendor on one contract benefit from Vonage's broader surface area. ## Pricing: advertised vs actual Vonage's publicly listed pricing for US domestic voice is roughly $0.00798/min, which looks competitive on paper. In practice, regulatory surcharges, compliance fees, number rental, and platform fees can push the real cost well above the listed rate. Enterprise pricing requires a sales conversation, with no self-serve transparency for larger volumes. Callr pricing is straightforward: - **Professional:** from €599/month, including call tracking, conversation intelligence, API access, and Callr Actions. - **Enterprise:** custom pricing for high-volume deployments with dedicated infrastructure and SLA guarantees. Callr's pricing is what it says it is — no hidden regulatory recovery fees, no surprise line items. ## Scale and reliability | Metric | Callr | Vonage | |--------|-------|--------| | Daily call volume | 2.5M+ calls/day | Not publicly disclosed | | Country coverage (numbers) | 220+ | 200+ (via aggregators) | | Infrastructure | Owned carrier network | Leased / Ericsson backend | | Founded | 2011, Paris | 2001, US (acquired 2022) | | Ownership | Founder-led, independent | Ericsson subsidiary | | Primary compliance | GDPR-native (EU entity) | US-first, EU via configuration | | Voice AI approach | Built-in conversation intelligence | AWS Nova Sonic partnership | | Low-code voice flows | Callr Actions | Vonage AI Studio | ## Migrating from Vonage to Callr Switching voice providers does not have to be painful. Here is a practical path. ### Phase 1: Parallel testing (weeks 1–2) - Provision Callr numbers in your target markets. Activation is same-day in most countries. - Route a slice of traffic (10–20%) through Callr while keeping Vonage as your primary. - Compare call quality, latency, and transcription accuracy side by side. ### Phase 2: Logic migration (weeks 2–4) - Translate your Vonage call-control logic into Callr Actions scenarios or direct API calls. - Callr's solutions team provides migration templates for common Vonage patterns — IVR trees, call queues, and webhook routing. - Port existing numbers where possible, and set up forwarding while porting is in progress. ### Phase 3: Cutover (weeks 4–6) - Shift the remaining traffic to Callr. - Decommission the Vonage integration. - Confirm that conversation intelligence and call-tracking data are flowing correctly. Most deployments complete in four to six weeks. Callr assigns a dedicated migration engineer for Enterprise plans. ## Who should choose Callr - **European companies** that need GDPR compliance without legal gymnastics. - **Scale-ups with high call volumes** that want carrier-grade quality and direct, responsive support. - **Product teams shipping voice features fast** — Callr Actions lets you define scenarios and deploy them in minutes. - **Teams that want to reach a human** when something breaks at 2 AM. - **Teams building AI voice applications** that want a provider-agnostic architecture rather than AWS lock-in. ## Who should choose Vonage - Enterprises that need video, voice, and messaging on a single contract. - US-regulated industries that require FedRAMP or HIPAA from their communications provider. - Organizations whose procurement wants a Fortune 500 parent on the invoice. - Teams already invested in AWS who want tight Nova Sonic integration. ## The bottom line The Ericsson acquisition made Vonage a safer choice for enterprise procurement and a less natural fit for everyone else. If you are mid-market or growth-stage — especially in Europe — you now face longer sales cycles, slower support, and a roadmap set by Ericsson's corporate strategy. Callr exists because voice infrastructure should be owned, not rented. Carrier-native architecture, EU-first compliance on owned infrastructure, founder-led agility, and transparent pricing define the alternative. For teams that ship fast and need voice to work across 220+ countries at 2.5 million calls a day, that is the difference. **Ready to test the difference?** Start a parallel deployment in minutes at callr.com — no sales call required for Professional plans. --- # What Is a Voice AI Agent? *2026-02-05 · Callr* A voice AI agent answers calls, understands intent, and acts on it automatically. See what they do, how they beat IVR, and where they fit your business. Every missed call is a missed opportunity. A voice AI agent is software that picks up the phone for you, understands what the caller wants, and takes the right action, all without a human in the loop. Instead of leaving callers in a menu or sending them to voicemail, it holds a real conversation and gets the job done. ## What a Voice AI Agent Does A voice AI agent uses artificial intelligence to answer, interpret, and respond to phone calls in natural spoken language. It can recognize what a caller is asking for, reply in context, and trigger downstream actions on its own. In practice, a voice AI agent can: - Answer inbound calls the moment they come in - Understand spoken language, not just keypad input - Route the call or handle the request directly - Collect the details you need from the caller - Trigger workflows such as CRM updates, bookings, and follow-ups Many businesses deploy them as virtual receptionists or as front-line agents that qualify inbound leads before a person ever gets involved. ## Voice AI Agents vs Traditional IVR Traditional IVR systems lean on rigid menus and keypresses: "Press 1 for sales, press 2 for support." Callers have to map their needs onto your menu, and anything outside that menu hits a dead end. A voice AI agent works the other way around. The caller speaks naturally, and the agent adapts to them. It handles open-ended questions, follow-ups, and unexpected phrasing, which makes it far more flexible and far more effective when an inbound lead is on the line. You stop losing callers to menu fatigue, and you capture intent you would otherwise never hear. ## Business Use Cases Voice AI agents earn their place wherever a phone call carries real value. Common use cases include: - Capturing calls that would otherwise go unanswered - Qualifying inbound leads automatically - Answering frequently asked questions around the clock - Booking and rescheduling appointments - Routing calls intelligently based on what the caller actually needs The result is consistent coverage: every caller gets a useful answer, even outside business hours and during peak volume. ## Pairing Voice AI Agents With Call Tracking A voice AI agent gets sharper when you connect it to call tracking. Together, they give you a complete picture of your inbound voice performance: - Identify which channel or campaign drove each call - Analyze caller intent across conversations - Measure how calls convert into outcomes - Attribute revenue back to the calls that earned it Instead of treating phone calls as a black box, you can see exactly where your best conversations come from and double down on them. ## Building One With Callr Callr lets you build and run voice AI agents on programmable voice, call tracking, and conversational intelligence, all on the same platform. You connect your agent to your own systems through a REST API and webhooks, so calls feed straight into your CRM, your booking tools, and your reporting. You keep control of the conversation flow while the agent handles the calls at scale. ## In Short A voice AI agent automates phone conversations with AI so your business can capture, understand, and act on every inbound call. It answers when you can't, qualifies the callers worth your time, and turns voice into measurable results, without adding headcount. --- # What Is Call Tracking? *2026-02-04 · Callr* Call tracking connects inbound phone calls to your marketing, so you can see which campaigns drive calls, leads, and revenue, and act on it. You can measure almost everything a customer does online: clicks, page views, form fills. The moment they pick up the phone, most of that visibility disappears. Call tracking closes that gap. It tells you where a call came from, what prompted it, and what happened during the conversation, so the calls your business depends on become as measurable as any click. ## What Call Tracking Is Call tracking is the technology that links each inbound phone call to the marketing campaign, channel, or page that produced it. It ties calls back to the customer journey and the campaigns that drive them, which turns voice leads into data you can count, compare, and act on. Instead of guessing which efforts make the phone ring, you know. ## How Call Tracking Works The mechanism is straightforward and runs in four steps: 1. You assign a dedicated phone number to a specific campaign, channel, or landing page. 2. A customer dials that number. 3. The call is logged, recorded, and analyzed with AI. 4. The resulting data flows into your analytics tools, CRM, or dashboards. Because each number maps to a known source, you can see exactly which channels generate calls, which calls become leads, and which leads turn into revenue. ## Why Call Tracking Matters Many teams invest heavily in digital marketing but cannot measure phone conversations with the same precision they apply to online activity. That leaves a large share of demand unaccounted for, especially in industries where buyers prefer to call. Call tracking gives you the tools to: - Measure the ROI of inbound and offline calls - Spot high-intent leads as they come in - Improve marketing attribution across channels - Direct acquisition spend toward what actually works Without it, your phone conversations stay disconnected from your performance metrics, and a real part of your results stays invisible. ## Call Tracking and AI Modern call tracking goes well beyond counting calls. With AI analysis applied to each conversation, you can: - Detect caller intent and call outcomes - Identify qualified leads automatically - Surface recurring topics and objections - Enrich CRM records without manual data entry This turns raw phone calls into structured business intelligence you can route, report on, and improve. ## A Practical Example A prospect clicks a paid ad and calls the number on your landing page. Call tracking attributes the call to that campaign, analyzes the conversation, recognizes a clear purchase intent, and marks the lead as qualified in your CRM. Your marketing team can then credit revenue to specific phone calls, not just to clicks. The result is a complete picture of what your spend actually returns. ## Putting Call Tracking Into Practice In practice, call tracking works best when it sits on top of programmable voice and messaging. With Callr, you can assign tracking numbers, analyze conversations with AI, and connect voice interactions to the systems and processes you already use through a REST API and webhooks. Callr Actions lets you build the call-handling logic in a scenario, so routing, tagging, and follow-up happen automatically and consistently. ## Conclusion Call tracking makes inbound phone calls measurable. It connects each conversation to the campaign behind it, analyzes what happened, and converts voice interactions into insights you can use. If your customers reach you by phone, call tracking is how you give those calls the same accountability as the rest of your marketing. --- # How Marketplaces Use Conversational Intelligence to Measure Leads *2025-12-25 · Callr* Learn how marketplaces use conversational intelligence to spot high-intent buyers, score leads from calls and SMS, and turn more conversations into sales. If you work in marketing or sales, you have almost certainly come across the term "conversational intelligence." It can sound like something out of the future, but it is already in use today, and it is changing how marketplaces operate. If you run a marketplace and you want a reliable way to track, measure, and ultimately convert your leads into paying customers, this guide is for you. ## What Is Conversational Intelligence? Start with the fundamentals. Conversational intelligence (CI) is the practice of analyzing conversations — across phone calls, SMS, and email — to pull out insights you can act on. Think of it as the layer that tells you what is working in your customer interactions and what is not. The point is not to listen in on conversations for its own sake. CI uses technology such as AI and machine learning to surface patterns, read intent, and measure outcomes. Instead of guessing which sales pitch or which answer to a customer question performs best, you make decisions based on real data. Here is a concrete example. Suppose you run an online home-services marketplace that connects homeowners with plumbers, electricians, and other professionals. A prospective customer calls your platform and asks: "How much does it cost to fix a leaking pipe?" You can analyze inbound and outbound calls and SMS handled by your sales team and capture the data that matters: call source, intent, budget, objections, and more. With conversational intelligence in place, your system reads the call as it happens and recognizes a high-intent lead — someone who is ready to book a service. From there, an AI agent can recommend the best response, informed by conversations that converted in the past. ## Why Marketplaces Need CI Marketplaces such as Bien Ici, Meilleurs Agents, or CoStar run on leads. They are built to connect buyers with sellers and service providers with customers. But not every lead carries the same weight. Some are ready to buy right now; others are still just looking. This is exactly where conversational intelligence earns its place. By analyzing the interactions between customers and sellers, CI helps marketplaces work smarter in several ways. First, it identifies serious buyers. Not every conversation ends in a sale, and CI examines interactions to separate the genuinely interested from the casual browsers. Second, it sharpens seller responses. The way a seller answers a question can decide whether a deal closes. CI shows you which responses persuade buyers and which ones fall flat. Third, it speeds up your replies. Fast answers make for happier customers, and nobody likes being left waiting. CI flags slow response times and points to ways you can tighten them. Finally, it shows you what actually works. If you want to know whether your campaigns are bringing in valuable leads, CI tells you where your leads come from and how many of them turn into customers — so you can measure your real return on investment. In short, conversational intelligence helps marketplaces convert more leads into sales, faster and with more precision. ## How CI Works Conversational intelligence rests on three core steps: 1. **Data collection.** Interactions are recorded or logged — with consent, always. This can include phone calls, live chat transcripts, and email exchanges. 2. **Data analysis.** AI-powered tools examine the data for keywords, sentiment, intent, and more. If a lead says "I need this urgently," for example, the system flags the conversation as high priority. 3. **Actionable insights.** The results are presented in a format you can use immediately — dashboards and reports — so sellers and marketplace managers can act on them. Consider a real-world case. You manage a real estate marketplace that connects buyers with agents. A buyer asks, "Is this property still available?" A CI tool can flag this as a high-intent lead. It can also suggest follow-up questions to keep the conversation moving, such as "Would you like to schedule a visit?" CI does more than surface your best leads. It can also reveal recurring customer concerns by reading the patterns across many conversations. If a large share of customers ask about delivery times or pricing, CI brings that trend into view, and marketplace managers can adjust services or pricing to stay competitive. ## Tools That Make CI Work To get the most out of conversational intelligence, you need the right tools to automate your communication. These tools track conversations, pinpoint valuable leads, improve customer interactions, and ultimately lift your conversion rate. Here is how they fit together. ### Connect CI to Your CRM and Marketing Stack For conversational intelligence to deliver, it has to work alongside the tools you already run. That is why effective CI connects to your CRM, marketing platforms, and analytics software — so you can manage customer interactions efficiently and make sure no lead slips through. With these connections in place, you keep every customer interaction in one place, which makes it far easier to follow conversations across calls, email, SMS, and chat. You can also measure marketing performance and see which ads, campaigns, or channels bring in the most engaged leads. And you improve collaboration by giving every team access to relevant, up-to-date customer insight. By connecting CI to the rest of your stack, you communicate better, work smarter, and convert more — without the extra effort. If you are wondering where to start, Callr can help. Callr is built to bring voice and SMS interactions into your marketplace and CRM, using a REST API and webhooks so the data flows where you need it. Callr can analyze your calls to measure lead quality and engagement, saving you and your team a great deal of time. ## Best Practices for Using CI in Your Marketplace If you are ready to put CI to work, a few practical steps will help you get there: 1. **Define your goals.** Be clear about what you want to improve. Are you after higher-quality leads, faster response times, or stronger conversion rates? A clear goal lets you put CI to use effectively. 2. **Train your team.** Make sure your sellers and service providers know how to use the system. The better they understand it, the more they can lean on it to close deals and improve the customer experience. 3. **Keep refining.** CI is not a set-and-forget project. Review the data regularly, see what is working, and adjust your approach to get better results over time. ## The Takeaway In a competitive market, marketplaces need every advantage they can find. Conversational intelligence is not a buzzword — it is a practical way to track potential customers and make everyone's job easier. With Callr, you are not just keeping pace with the competition; you are getting ahead of it. So, are you ready to turn your marketplace into a lead-winning engine? To see how Callr can help, take a look at the Bien Ici use case. It is time to make smarter choices. --- # The Handbook for Safe User-to-User Communications in the Sharing Economy *2025-08-12 · Callr* How peer-to-peer marketplaces build trust and safety into user communications — with SMS, voice, number masking, and identity, plus advice from P2P operators. Call it the collaborative, gig, peer-to-peer, or sharing economy — whatever the label, these platforms now operate at global scale. Their growth came with hard questions: regulation, working conditions, fair distribution of value, and whether "sharing" is the right word at all. But for anyone building a marketplace, one challenge sits above the rest: how do you let two strangers communicate safely? As a communications platform, our role in helping these marketplaces grow comes down to two things — matchmaking between buyers and sellers, and, just as importantly, keeping those interactions secure. This handbook walks through the decisions that shape a marketplace notification and communication system, with practical guidance and input from people who have run peer-to-peer platforms. ## Meet the operators Four marketplace practitioners shared their views throughout this handbook: - **Curren Bates** — vehicle strategy lead at a micromobility company, and former Director of Marketing at a bike-sharing platform. - **Patrick Nangle** — CEO of a car-sharing co-operative in British Columbia, and former CEO of a national freight delivery service. - **Esther Martos Carrión** — UI/UX expert and sharing-economy researcher who has worked with shared-mobility platforms built on blockchain and smart contracts. - **Adam Broadway** — marketplace expert and CEO of a service for building peer-to-peer and business-to-business marketplaces. ## Building trust into a peer-to-peer platform ### What makes a peer-to-peer platform work? Regulators and researchers have boiled marketplace success down to three conditions. A platform tends to work when: 1. It is liquid — there are enough buyers and sellers active at once. 2. It enables matchmaking between buyers and sellers in real time. 3. The transactions taking place on it are safe. That third point is where communication design matters most. Trust mechanisms — anonymous numbers, email verification, in-app chat, or two-factor authentication over SMS — let you build a safe environment. Which ones you reach for depends entirely on your business model and the kind of experience you are creating. Different marketplaces create digital trust in different ways, and the mechanism usually scales with the stakes of the exchange. Low-stakes classifieds sites get by with minimal trust signals. Marketplaces built on ratings add reputation but light moderation. Platforms that connect people for high-stakes offline experiences — riding in a stranger's car, staying in a stranger's home — invest heavily in trust: ratings, moderation, verified IDs, and insurance. A useful mental model breaks trust-building into six pillars: declaring information, rating systems, financial commitment from users, encouraging active members, moderated environments through third-party verification, and identity verification through social profiles. ### User identification The hard questions are old ones, sharpened by scale. How do you make sure digital identities reflect real-world ones — and do you even want them to be the same? How do you recreate online the trust that builds naturally face to face? How do you stop someone who behaved badly in one community from showing up again under a new name? A central decision is how much of a user's real contact information — phone number, email, social profile, even full name — should be visible to other users. #### How much do you really need to know? Some argue for total transparency, on the theory that mutual exposure keeps everyone honest. In some cases knowing real identities genuinely helps: linking a social profile, or requiring an institutional email address, can reassure users about who they are dealing with, or keep a platform inside a closed community. Letting users sign in with an existing social account and surface mutual connections is a common way to do this. #### Storing contact information is a risk in itself The flip side is that exposed contact information invites abuse. Scammers harvest phone numbers for phishing, and the disinhibition of online interaction can spill into harassment. The issue is one of balance. As one privacy research group put it, platforms have to understand the relationship between identity, anonymity, obscurity, and reputation. They need to give users transparency into how their information is accessed — while offering enough obscurity from other users to protect privacy. In short: sometimes a buyer and seller should know each other's real identities, and sometimes they should not. A communications platform is well placed to help you manage that obscurity-versus-identity trade-off — for example, by connecting two people through masked phone numbers so they can talk without ever exchanging personal details. Newer approaches to identity and reputation continue to evolve, including systems that let a user keep a persistent, verifiable history under a pseudonym, separate from their real-world identity. The general direction is clear: verifiable trust does not always have to mean exposing personal data. #### Operator's view — Esther Martos Carrión We asked Esther, a UI/UX expert and sharing-economy researcher, for her take on the anonymity-versus-transparency debate. *"This is a constant debate. Personally, I think societies are moving toward transparency. From my research, newer generations are less concerned about privacy than previous ones — people share their personal lives every day, and they enjoy it. You can see how many platforms log users in through existing social or payment accounts, which means platforms are increasingly networked and share information between them. Reputation is starting to move between platforms too, and payments are next. My honest view is that buyers and sellers will keep their social profile as their identity."* ### Platform boundaries Once you have decided how much contact information you actually need, the next question is which channels you use — both to talk to your users (notifications, announcements, events) and to connect users to each other. Before the channels themselves, though, there is a bigger question: should communication between users happen on your platform at all? #### Keeping conversations on the platform For most marketplaces, keeping conversations on-platform is the better choice for three reasons: 1. **It prevents side-stepping.** If users can talk freely off-platform, nothing stops them from closing the deal elsewhere to avoid your fees. 2. **It makes conflict resolution possible.** Whether the exchange is text or voice, you have access to the record from both sides. 3. **It produces useful signal.** Analyzing exchanges helps you spot friction and prioritize what to build next. That said, locking users in without giving anything back tends to breed frustration. The platforms that do this well make staying on-platform clearly worth it — through insurance, buyer protection, refunds, professional accounts, and similar benefits. A common pattern is to keep the conversation on-platform until the deal is closed, then release contact details so the two parties can coordinate the handoff directly. #### The balance between usability and safety Platform boundaries capture the core tension of any peer-to-peer service: the experience must be as frictionless as possible, while the operator still enforces the checks that prevent scams and abuse and keep users safe. #### Operator's view — Curren Bates We asked Curren, who has led strategy and marketing at mobility platforms, how he thinks about user communications. *"We encourage communication by whatever means works. The key is that, for the safety of both parties, we don't allow that exchange to happen until a rental has been booked through the platform — that's when the protection guarantee kicks in. Beyond that, our in-house messaging exists to give members two things: convenient, instant communication across both email and mobile, and organized record-keeping of their rental conversations, in case anything comes up later. You could keep those records yourself, but it's more of a headache."* *"Advice for designing a notification system that's both convenient and safe? Hire good engineers, trust your team, and learn from your mistakes. It sounds cliché, but the market will lead you in the direction you should be heading — so listen."* ## Designing your notification system Enabling real-time matchmaking and safe transactions comes down in large part to choosing the right notification system. Speed and responsiveness are critical on a peer-to-peer platform. Should you use personal email, in-app messaging, SMS, anonymous phone numbers — or a mix of all of them? Below is a quick read on the trade-offs of the channels marketplaces use most. ### Voice - **Benefits.** Voice is synchronous and personal, and it is efficient for urgent or time-critical conversations. Everyone knows how to make a phone call. - **To consider.** You can let users swap numbers directly, but that comes with privacy risks. Using a communications API, you can connect two people by phone while keeping their real numbers private and retaining a record of the call. - **Recommendation.** Calls are the most reliable channel for emergencies and situations that need a real conversation. ### SMS - **Benefits.** SMS has the best open rates, read rates, and time-to-read of any channel, which makes it the strongest pick for time-sensitive alerts. - **To consider.** As with voice, avoid having users swap numbers directly — use a number-masking service to connect them instead. - **Recommendation.** SMS is ideal for time-critical alerts. It also works without a smartphone, which can matter depending on your audience. ### In-app messaging - **Benefits.** Users can exchange messages easily and safely, with a degree of privacy maintained until trust is established. - **To consider.** It is not ideal for time-sensitive messages, and not everyone keeps notifications enabled — plan for alternatives. - **Recommendation.** Great for synchronous, on-platform conversations; weaker when the exchange is asynchronous. ### Email - **Benefits.** Everyone already has email, and the address itself can support checks (for example, accepting only a given domain). - **To consider.** Keep users' email addresses out of public view, and remember that email makes off-platform deals easier. - **Recommendation.** Convenient but riskier — best reserved mainly for service notifications. The biggest factor in choosing channels is your audience. ### Operator's view — Adam Broadway We asked Adam, a marketplace expert and CEO of a marketplace-building platform, which channels he would recommend. *"All of the above — including video calls and third-party integration points, plus customer-service tools. Easy communication between guest and host, buyer and seller, lister and enquirer is critical, including escalation rules for the cases where someone doesn't follow up."* *"For some interactions, instant messaging is fastest and personal enough to answer simple questions. For others, click-to-call with masked numbers is what's needed, because the caller wants a deeper conversation than text can handle. Calls made through a communications platform can also be recorded for quality and training, so the operator can review conversations and improve the experience."* *"The platform behind the marketplace also needs a flexible workflow engine, so that 'you have a new inquiry' alerts can go out as email, SMS, or in-app — and so reminders escalate across channels if a follow-up doesn't happen in time. Future-proof your channels with an API layer, so third-party services, CRM, and service-desk tools can all be part of the strategy."* ## Control mechanisms that maintain trust Safety is arguably the heart of the debate around the sharing economy, and the hardest part to get right. Opinions differ on how to keep both buyers and sellers safe, and even on who is responsible. Regulators tend to take a firm line, but it is plainly in the platform's own interest to reduce the real — and perceived — risk of using the service. There are several ways to do that. ### Rating systems If your providers are individuals, the most valuable thing you can offer is trust and safety. People hesitate to trust strangers: if I lend my car or my drill to someone I have never met, how do I know they won't damage it or disappear with it? That distrust creates friction in any consumer-to-consumer marketplace — and the marketplace can reduce it by acting as a trusted middleman. Reputation rating systems have become a cornerstone of these platforms. They do reduce information asymmetry, but they have real limits: 1. **Ratings skew high and toward extremes.** People are more likely to review a particularly good or bad experience, and many skip negative reviews to avoid confrontation — which skews the results. 2. **Ratings can be gamed.** Fake reviews, positive and negative, are common, and some users avoid honest negative feedback for fear of retaliation. 3. **Experience matters.** Newer users are less practiced at reading between the lines of how reviews are written. 4. **Cold starts hurt newcomers.** A brand-new user has no track record, which makes it hard to build a reputation and get going. 5. **Reputation milking.** Someone about to leave the platform may feel they can trade on their good score without consequences. Rating systems make a marketplace safer, but they should never be the only trust mechanism you rely on. #### Operator's view — Patrick Nangle We asked Patrick, CEO of a car-sharing co-operative, how he keeps users safe. *"Our members own the co-operative. The platform simply lets them use the vehicles and contribute to the cost of operations. We ask members to return each vehicle on time, clean, and at least a quarter full of fuel — a courtesy to the next person. Members who don't are subject to fines, and we count on the next user to flag any issue. The fines are there to encourage better behaviour, not to be profitable. Our updated app includes photo functionality to make reporting easier."* ### Platform intervention A rental marketplace can offer insurance: if an item is stolen or broken, you cover it — but only when the payment ran through your own system. Coverage scales with the value at stake, from high limits for vehicles down to lower limits for lower-value gear like cameras and equipment. Some ridesharing platforms charge a commission and justify it precisely by the insurance they provide. Many platforms also intervene directly to build and protect trust: 1. **Curate who gets in.** Set criteria for who can use the platform — a ride-hailing app, for instance, can require a valid driver's licence. 2. **Offer refunds.** A reliable way to reassure unhappy customers. 3. **Provide insurance.** Helps a home-sharing or rental platform feel more secure. None of these is a complete answer. Curation can't screen out every bad actor, and refunds and insurance only help after something has gone wrong. Rating systems and platform intervention together still can't guarantee a perfectly safe experience — which is exactly why communication design and identity controls matter so much. ## Parting thoughts We hope this handbook helps you understand the challenges of direct user-to-user communication and how to handle them. Here are ten takeaways for designing better peer-to-peer communication systems, followed by a last round of advice from the operators. ### Ten principles of peer-to-peer communication 1. Encourage users to keep communication on the platform rather than posting personal phone numbers or emails publicly. 2. In-app chat and messaging help keep conversations on-platform — for both security and insurance reasons. 3. High deliverability and open rates make SMS the right call for time-sensitive alerts, on-the-go users, or audiences without smartphones. 4. Voice is easy to use and the right choice when your platform needs personal, synchronous conversation. 5. A communications platform can add a valuable layer of privacy or verification through masked numbers and two-factor authentication. 6. Offer a variety of secure ways for users to communicate. 7. The higher the stakes of your model, the more trust mechanisms you need. 8. Transparency versus anonymity is an open debate — what matters is choosing trust mechanisms that fit your platform, whether that's 2FA ID checks, social sign-in, masked numbers, ratings, or insurance. 9. Be honest about what your platform does. If your model isn't really about sharing, don't market it as such. 10. Listen to your users, and model your notification system around the channels they already use and the interactions you are building. ### Final advice from the operators **Curren Bates.** *"Trust starts with you, the founder. Show your community how you expect people to treat each other, every day. Maintain exemplary support, especially early on when reviews and backlinks are still scarce. Listen to what your community asks for, take cues from established platforms — and remember there's no such thing as too much trust."* **Patrick Nangle.** *"Don't claim to be part of the sharing economy if you're not — you'll lose trust fast if you aren't authentic. Decide whether your platform genuinely facilitates sharing or is really an exchange for buying and selling. There's nothing wrong with running a business that facilitates trade for profit; just don't call it sharing if that's what it is."* **Adam Broadway.** *"Communication is the key to success in any relationship, online or off. Give your community more ways to communicate, and don't worry about them 'taking the deal off-platform.' The more conversations you enable — through chat, email, text, phone, or video — the more engagement you'll have, which leads to more growth and more conversion. Building on top of existing, respected platforms rather than from scratch also helps you avoid security gaps, because you inherit others' best practices."* **Esther Martos Carrión.** *"Early on, it's better to grow through social networks — it brings a lot of visibility and new users, and it's less invasive than email or SMS. Once the platform is consolidated and has a community, you can move to channels like newsletters and live chat. We also built an internal social space with different channels where our users could ask questions, raise doubts, and connect with peers."* --- # How to Build Trust and Communication into a Peer-to-Peer Marketplace *2025-07-29 · Callr* Practical advice for marketplace founders on choosing communication channels, real-time notifications, and trust mechanisms that keep buyers and sellers engaged. The way buyers and sellers communicate can make or break a peer-to-peer marketplace. Strong notification systems, trust signals, and security mechanisms aren't optional extras — they're what keep users coming back. To dig into how founders should approach these decisions, we spoke with Adam Broadway, a marketplace specialist and founder of Marketplaceplatform.com. The conversation below should help you decide which notification systems and trust mechanisms fit your platform, based on your industry, your users, and your business model. ## Which communication channels should a marketplace offer? When we asked which channels — email, in-app messaging, SMS, phone calls, push notifications — work best for putting marketplace users in touch, Adam's answer was simple: it depends on the conversation, and you should keep your options open. > Future-proof your communication channels by adding an API layer, so third-party services can become part of your overall communication strategy. His advice was to support all of the above, including video calls and integrations with services like Callr, Slack, and customer-support tools. Ease of communication between guest and host, buyer and seller, or lister and enquirer is critical — and so are the escalation rules that handle the exceptions, the cases where a follow-up never happens. For some interactions, instant messaging is the fastest way to answer a simple question and still feel personal. For others, [click-to-call with number masking](/resources/features/communication/) is the better fit, because the caller needs a real conversation that email or text can't deliver efficiently. Calls placed through a CPaaS provider can also be recorded for training and quality purposes, so the marketplace owner can review conversations to improve the user experience and FAQ content. The platform powering the marketplace also needs a flexible workflow engine. Alerts like "you have a new inquiry" should be deliverable as email, SMS, or in-app notifications. Those same workflow rules should handle reminders: if a follow-up hasn't happened in time, the system can escalate through other channels to make sure the message reaches the user. ## When is one channel better than another? Different marketplaces call for different defaults. A ride-matching service might lean on SMS, while a home-sharing platform might prefer email or in-app messaging. > Find out which channels your users actually prefer, and let their answers guide you. Adam's core principle: the choice should be based on the needs of the end customer, not on what's easiest for the marketplace owner or the developer building the solution. Ask your user base which channels they're most likely to use, and design around the answer. A few examples: - **Elderly-care marketplaces** are often best served by a click-to-call feature. - **Expert and consulting marketplaces**, where conversations get complex, benefit from a video-call integration. - **General product marketplaces** can usually get by with instant messaging, email, or chat. It's also worth running a return-on-value analysis: weigh the cost of a given communication framework against the outcomes it drives — a purchase, a new signup, higher subscription revenue, lower support costs — and let that inform which methods you enable. One word of caution. If your main worry is "letting users talk directly might mean they take the deal off-platform" — so-called platform leakage — you're focused on the wrong thing. The real question is: what value are we providing that makes our community *want* to keep their communication and transactions on the marketplace? ## Getting real-time notifications right When we asked what advice he'd give founders on real-time notifications between buyers and sellers, Adam returned to that same principle. > Don't burn time trying to stop the small share of users who'll go off-platform. They'll always find a workaround. Spend that time adding value so they don't want to leave in the first place. Focus on the needs of your buyers and sellers, guests and hosts, listers and enquirers. Ask yourself: how can I make communication between my users as easy as possible? And don't reinvent the wheel — there are plenty of solid services for every kind of communication, so you don't need to build the technology from scratch. Building on platforms that have already integrated these capabilities is the more efficient path. Voice and SMS providers like Callr let marketplaces add automated notifications to their products without rebuilding telephony infrastructure. With a [REST API and webhooks](https://docs.callr.com), you can trigger an SMS or a call from your own workflow and react to inbound events as they happen. Finally, accept that a small percentage of users will always try to cut out the marketplace's commission and deal directly. Trying to prevent every such case is a losing battle. Your time is better spent on value and service that makes people genuinely want to stay — which may mean revisiting your business model. ## Anonymity versus transparency Should buyers and sellers stay anonymous, or should their real identities be visible? We asked Adam where he lands on the debate. > For marketplaces that are "communities of interest," more explicit trust and transparency may be required — phone verification, linked social accounts, or flagging suspicious activity. Identity theft and fraud keep rising, so protecting everyone in the marketplace matters — but how you do it depends on the type of marketplace. - In a **community of practice** — where everyone is, say, a vetted career professional — implicit trust already exists. Membership itself signals that users have the credentials to participate. - In a **community of interest** — where participants are more casual and ad hoc — you'll likely need more explicit trust mechanisms: phone verification, social-account linking, and tools to flag potential phishing or fraud. Phone verification is a common starting point. Many sharing-economy platforms use two-factor verification by SMS, among other safety measures, to confirm that users are who they claim to be. Technology can help in several ways — by surfacing known patterns in user behavior so administrators can manage fraud by exception, or by flagging cases where someone doesn't look like who they say they are. You can also build a "middle-ground" rule into the marketplace: once a user has verified their account over time, linked social accounts, and met the community's bar for "proof of trust," they earn access to more personal information. One of the most powerful approaches is peer-group analysis, where a member's standing is validated by several other trusted, interconnected members of the community. This mirrors how trust works offline, and tools exist to turn those peer relationships into credibility scores that can be quantified in a more automated way. ## Building trust and security among your users We closed by asking what advice he'd give founders on creating trust and security across their platform. > The more ways you let people talk — IM, chat, email, text, phone, video — the more engagement you'll see, and the more growth and conversion that follows. Communication is the key to any relationship, online or off. Give your community more ways to connect, and stop worrying about them taking the deal off-platform. Every additional conversation channel you offer drives more engagement, and more engagement leads to more growth toward your business goals. Building on top of established, respected platforms — rather than starting from the ground up — also closes security gaps, because you inherit the lessons and best practices others have already learned. --- # Overcoming P2P Challenges (Part 2): Trust and Security *2025-07-15 · Callr* How peer-to-peer marketplaces build trust and security — 2FA, masked numbers, reputation systems, moderation — with practical advice from platform founders. Connecting people and earning their confidence is the whole point of a peer-to-peer platform. Without trust, an online marketplace has nothing to stand on. In Part 1 we looked at how communication shapes the P2P experience; here we focus on the harder problem underneath it: making strangers feel safe enough to transact with one another. Building security into a peer-to-peer platform is not optional. The notification and verification systems you reach for — anonymous numbers, email confirmation, in-app chat, SMS-based two-factor authentication — are the foundation of a safe ecosystem. Which mechanisms you choose depends on your business model and the experiences you want to create. ## How the stakes shape the trust model Different marketplaces invest in trust in proportion to what's at risk in each exchange. A classic way to frame this: - **Low stakes, low trust.** Classifieds-style platforms keep moderation light and let users sort it out themselves. - **Ratings with light moderation.** Resale and handmade-goods marketplaces lean on buyer and seller ratings, with the platform stepping in only when needed. - **High stakes, high investment.** Ride-sharing and home-sharing platforms put real money, property, and offline encounters on the line — so they invest heavily in ratings, moderation, verified IDs, and insurance. A widely cited framework for P2P trust sets out six pillars worth designing around: - **Declaring information** — encourage users to share who they are. - **Rating systems** — let the community vouch for one another. - **Engagement through financial commitment** — skin in the game raises accountability. - **Active members** — a live, participating community self-polices. - **Moderated environments** — third-party verification backs up user claims. - **Social linking** — connect identities to existing social profiles. The pattern is consistent: the more a transaction can go wrong, the more verification you should build in. ## What platform builders actually do To ground this in practice, we collected perspectives from people running peer-to-peer businesses on how they build trust and security — and where they land on the long-running transparency-versus-anonymity debate. ### Why mobile 2FA plus social verification A marketing director at a peer-to-peer gear-rental platform put the case for layered verification plainly: > Trust is paramount in the sharing economy. Without it, you can't scale. Mobile two-factor authentication is table stakes for any P2P business that's serious about verifying identities and building a community people can rely on. Would you hand a $5,000 piece of equipment to someone unwilling to confirm a basic, secure phone number? Neither would we. On advice for founders: > Trust starts with you. Model the behavior you expect from your community, every day. Keep your customer service exemplary — especially early on, when reviews and reputation are thin. Listen to what your users ask for, learn from more established platforms, and remember that when it comes to loyalty and satisfaction, there's no such thing as too much trust. A practical takeaway here: mobile 2FA and masked phone numbers are exactly the kind of capability you can add through a telecom API rather than building from scratch. ### Designing rules instead of penalties The CEO of a member-owned car-sharing co-operative described a different model, where ownership itself does much of the trust work: > Our members own the co-operative. The platform just gives them a way to use the vehicles and share the cost of running them. We ask members to return vehicles on time, clean, and fueled. Those who don't face fines — designed to encourage better behavior, not to make money. Our app includes photo functionality to make reporting issues easy. On anonymity versus transparency: > With a member-owner structure, that's a non-issue for us. In a genuinely collaborative enterprise, identity shouldn't be a problem. And on positioning: > Don't claim to be part of the sharing economy if you're not. You'll lose trust fast if you're not authentic. Decide whether your platform truly facilitates sharing or is simply a marketplace for buying and selling. There's nothing wrong with building a business that facilitates trade for profit — just don't call it sharing if that's what it is. ### Reputation systems and a human touch A co-founder and researcher working on sharing-economy marketplaces argued that reputation, backed by real human support, does the heavy lifting: > Reputation systems are what work best in the sharing economy, at least for now. It's also essential to offer quality customer service and attend to each request personally — users trust a platform more when they can reach a real person. Integrated live chat is genuinely useful for that. On the transparency debate: > This is a constant tension — transparency or privacy? My sense is that societies are moving toward transparency. Newer generations are less worried about guarding their privacy; people share their lives every day and enjoy it. You can see it in how many platforms let you log in with an existing social account, so platforms increasingly network and share information with one another. Reputation will travel from platform to platform, and payment systems are next. Profiles people already maintain will increasingly serve as their identity. ### Keep the conversation on your platform A marketplace-platform founder made the case that more communication channels, not fewer, drive growth: > Communication is the key to any relationship, online or off. Give your community more ways to talk to each other and don't worry about them "taking the deal off the platform." The more conversations you enable — instant messaging, chat, email, text, phone, video — the more engagement you'll see, and engagement drives growth and conversion. Building on top of established, respected platforms rather than from the ground up also helps you avoid security holes, because you inherit other people's hard-won lessons. ## Key takeaways - Offer a range of secure communication options, and meet users on the channels they already use. - Scale your trust mechanisms to your risk profile: the more a transaction can go wrong, the more verification you need. - The transparency-versus-anonymity question has no single answer — what matters is choosing the right mix for your platform, whether that's 2FA and ID checks, social login, masked numbers, reputation systems, insurance, or a combination. - Be honest about what your platform is. If your model isn't really about sharing, don't market it that way. - Listen to your users and design your notifications and verification around the interactions you're actually building. ## Build trust into your platform with Callr Most of the trust mechanisms above — SMS-based two-factor authentication, masked phone numbers that protect both parties, call tracking, and programmable messaging — are voice and SMS capabilities you can add through Callr's REST API and webhooks. Callr runs on its own EU carrier infrastructure with EU data residency by default, so the communications layer that underpins your users' trust stays secure and compliant. [Talk to us](/contact/) about adding secure communication to your peer-to-peer platform. --- # Overcoming P2P Challenges (Part 1): Choosing the Right Notification System *2025-07-01 · Callr* Email, in-app chat, SMS or voice? A practical guide to picking notification channels that keep your peer-to-peer marketplace fast, safe and trusted. Peer-to-peer platforms live or die by how well they connect the two sides of a transaction. Strip the analysis down to its essentials and a marketplace works when it stays liquid, when it matches buyers and sellers in real time, and when the transactions it facilitates feel safe. Real-time matching and safe transactions both rest on the same decision: how you notify your users. Should you rely on personal email, in-app messaging, text messages, anonymous phone numbers, or some combination of all of them? And how do you build trust across your community while you're at it? This first part walks through the strengths and trade-offs of the notification channels most marketplaces use. Part 2 looks at trust in P2P platforms more broadly, with on-the-ground advice from founders who have built these systems themselves. ## Notification systems, channel by channel ### Personal email Email is the simplest way to let users get in touch or validate an account. **Where it helps:** It lets you keep a service inside a defined community — for example, by requiring a university or company email address to sign up. Users receive alerts on a channel they already check, and you ship no new infrastructure to support it. **What to watch for:** For liability and insurance reasons, most platforms want communication to stay on the platform. Publishing personal email addresses exposes users to scammers who scrape sites for contact details and then flood them with spam or fraud attempts. A common scheme pushes people to talk off-platform by email, then collects payment for goods or services that never existed. Transactions that bypass the platform are usually not covered by your protection or insurance, so the victim absorbs the loss. And if your business model takes a commission, swapping contact details gives users an easy way to skip the fee once they've found each other. The pattern behind most marketplace scams is the same: at some point the fraudster insists on moving the conversation to direct email or phone, or steers the other party to a different site to finish the deal. **Bottom line:** Personal email is a fine way to verify identity at sign-up or to keep a curated community closed. But letting users post their personal address publicly invites security and insurability problems. Encourage members to be wary of anyone who pushes hard to move the conversation off-platform, and never to send money outside it. ### In-app messaging and email You can still let users reach each other while cutting the security risk: keep the conversation inside your platform so people don't have to share real contact details, at least until they've built up trust one-to-one. In-app messaging — chat or email — is the route many well-known marketplaces have taken. Beyond connecting two users, in-app chat also gives your own support team a fast way to help customers in real time. **Where it helps:** Users communicate easily and safely on a channel they already understand, with a layer of privacy that lasts until trust is established between two people. **What to watch for:** Match the channel to how urgent the message is. In-app email works well for notifications that aren't time-critical, but transactional email open rates are modest, so don't rely on it for anything that has to be seen immediately. In-app chat is the better fit for synchronous, time-sensitive exchanges where two users are talking in real time. The catch: in-app messages depend on push notifications, in-app badges or email alerts to surface, so there's always a chance they aren't read right away — a silenced notification or no connectivity is enough to delay it. **Bottom line:** If in-app messaging is right for your platform, don't build it from scratch. Plenty of components exist to add chat or messaging, so your engineers can integrate rather than start a project from zero. ### Text messages SMS is an immediate, near-universal way to alert users about time-sensitive events. That makes it ideal for the "business-critical" moments of on-demand services — a driver arriving for a ride, an order dropped at the door for a delivery. Text also fits situations where the user is on the move and nowhere near a computer. Because you don't need a smartphone, Wi-Fi or mobile data to receive one, SMS delivers and gets read at very high rates: the large majority of texts are opened within seconds of arriving. Users also keep a tidy record of the exchange in their message thread. The same caveat as email applies, though: letting users post or swap personal phone numbers can reproduce the same risks. How much that matters depends on your model and the trust-and-safety measures you've put in place. Some people feel safer with full transparency, where everyone's real contact details are visible. Others want a privacy layer, at least until one-to-one trust is established. This is where a CPaaS (Communications Platform as a Service) provider earns its keep. You can offer SMS or voice while issuing dedicated or anonymous numbers that add a privacy layer, and you can layer on security measures like two-factor authentication, where a user confirms their number and account with a short code sent by text. **Where it helps:** High open and read rates; great for time-sensitive alerts to users on the go, and for 2FA. **What to watch for:** Letting users trade personal numbers is simpler upfront but can lead to phishing, harassment and scams that damage how your brand is perceived. The point is to build trust in *your* platform specifically, not just in the marketplace model in general. Unless you have very high in-community trust or you vet every new member carefully, integrating a CPaaS API to deliver SMS with dedicated or anonymous numbers gives you the convenience of text plus an extra layer of privacy. **Bottom line:** If you need to reach users in real time — especially when they're away from a computer — SMS is a smart default. Factor in your audience: if many of them don't use smartphones, lean on text over in-app or email. For all but the most tightly closed platforms, sourcing anonymous or dedicated numbers through a CPaaS API adds a layer of safety and helps you avoid harassment, fraud and phishing. ### Voice For some interactions, chat and text aren't enough — users need a secure, easy way to talk. You can do that by letting them publish a personal number, by adding click-to-call, or by using a voice API that connects calls through anonymous numbers. **Where it helps:** Voice is synchronous, personal and effortless for anyone to use, which makes it a strong choice for emergency notifications. As one of our clients in elderly-care monitoring put it, older generations aren't always comfortable with apps, push notifications or even SMS — but a phone call is familiar to everyone and remains the most reassuring, reliable channel in an emergency. **What to watch for:** As with email and SMS, users who swap personal numbers may expose themselves to risk. A CPaaS provider that supplies anonymous or dedicated numbers — and can record interactions — adds privacy and can provide evidence if a dispute ends up in legal territory. ## Advice from people who've built it We spoke with several marketplace founders and operators about how they handle notifications. Their insights still hold up. **A marketing director at a bike-rental marketplace, on in-app messaging:** "We encourage communication by whatever means works, but for the safety of both parties we don't allow that exchange to happen until a rental is booked through us — that's when our protection guarantee kicks in. Our in-house messaging is there to give members convenient, instant communication across email and mobile, and an organized record of their rental conversations in case anything comes up." His advice for building a notification system that's both convenient and safe: hire good engineers, trust your team, and learn from your mistakes — the market will point you where you need to go, so listen. **A CEO at a car-sharing co-operative, on which channels to offer:** "We're member-owned, running a platform that lets thousands of members share a fleet of vehicles. Members can book online, in the app, by phone or by email. Self-serve interfaces are the most economical, but to be inclusive we offer several ways to get in touch — not everyone has a smartphone. We staff our own contact centre for calls and emails, because when something needs immediate attention, an accident, a late return, a car that can't be found, members have to reach us fast and get help." **A co-founder of a food-sharing platform, on marketing the service:** "Early on, it's better to advertise through social networks — it brings visibility and new users, and it's less invasive than email or SMS. Once the platform is established and has a real community, you can move to channels like a monthly newsletter or live chat. We also built an internal community space where users could ask questions, resolve doubts and connect with other members." **A founder of a marketplace-building platform, on matching notifications to platform type:** "Easy communication between the two sides is critical, including escalation rules for the cases where follow-up doesn't happen. For some, instant messaging is fastest and personal enough to answer simple questions. For others, click-to-call with number masking is needed when the caller wants a deeper conversation than email or text allows. Calls placed through a CPaaS provider can also be recorded for training and quality, so the operator can review conversations to improve the experience and the help content. The underlying platform needs a flexible workflow engine, so a 'you have a new message' alert can go out by email, SMS or in-app — with reminders and escalation across channels if follow-up is late. Future-proof your channels with an API layer, so third-party services like chat, CRM and service-desk tools can plug into the overall strategy." ## Key takeaways - Keep communication on the platform — encourage users not to publish personal email addresses or phone numbers. - In-app chat and messaging help keep conversations on-platform, which matters for both security and insurance. - High deliverability and open rates make SMS a strong choice for time-sensitive alerts, for users on the move, or for audiences who may not have a smartphone. - Voice is effortless to use and the right call when your platform needs personal, synchronous, real-time contact. - A CPaaS provider adds a valuable layer of privacy and verification through anonymous or dedicated numbers and two-factor authentication. Read Part 2 of this guide for advice on building trust across your peer-to-peer platform. --- # What Is an API? A Plain-English Guide *2025-06-19 · Callr* A clear, jargon-free explanation of what an API is, how APIs and webhooks work, with everyday examples and how Callr uses both to automate workflows. You have almost certainly come across the term "API" — maybe from a developer friend, maybe in a tech article. Something to do with connecting data, right? This guide is for anyone who has ever wondered, out loud or quietly, what an API actually is. We will keep it free of jargon, lean on everyday examples, and show how APIs and their close cousin, webhooks, power the automation you rely on every day. ## What does API stand for? API stands for **Application Programming Interface**. Three words that sound more intimidating than the idea behind them. By the end of this article, each one will make sense — and you will start to notice APIs working quietly behind almost every app you use. ## What is an API, really? The first thing to understand is that an API is an **interface**. An interface to what? To an application. And who uses it? Other programs — not people. That is the key point: APIs are consumed by software, not by humans clicking buttons. So here is a clean definition: **an API is an interface that one program uses to interact with another application.** Or, put even more simply, APIs let computers talk to each other. A useful analogy is a wall socket. To dry your hair, your hairdryer needs electricity. You are not going to stick your finger into the wiring to pull out the current — that would not dry your hair, and it would be dangerous. You need an interface that makes the electricity safe to access and use: the socket. And you do not touch the socket directly either; you plug in the hairdryer. The plug draws current through the socket to power the device. Map that onto software: you are the person using your computer, the hairdryer is the program, the **socket is the API**, and the electricity is the application providing the data or service. "Drying your hair" is whatever the program was built to do. One word of caution: an API is not hardware. It is just another piece of software running on a server — a set of agreed-upon rules that both sides follow so they can exchange information reliably. ## Some API examples Let's see APIs in action. Imagine you manage content for a website that lists things to do in a city. For every event you publish, you want to show a map with a pin marking the venue. You have a few options: 1. Look up the latitude and longitude of each address by hand and plot it yourself. 2. Ask a developer to write a custom line of code for every single address. 3. Use a service that, through a mapping provider's **geocoding and maps APIs**, fetches the coordinates and drops a ready-made map onto your page in seconds. Option 3 is the only one a sensible person would choose. Here is what happens when you use it: your content manager types an address into a form in the back office. Hitting "enter" sends small packets of data — over Wi-Fi, then through the physical cables of the internet — to the provider's servers. Those servers interpret the request, look up the coordinates, and return them in a machine-readable format such as **JSON** (thanks to the geocoding API). The map and pin then render on your page in a format people can read. That single request saves both your content manager and your developer a lot of work. This is one of the main advantages of an API: it lets the end user do something useful while sparing programmers the tedious, repetitive coding it would otherwise take to build the same thing from scratch. The more an API turns a complex, oft-repeated process into a few lines of reusable code, the more productive everyone becomes. This is why APIs are everywhere. Mapping providers, social platforms, payment processors, messaging services — they all expose APIs so developers can embed maps, enable "sign in with…" buttons, accept payments, and far more. The possibilities run from simple to genuinely sophisticated. Take our events website again. Suppose a concert gets cancelled and you need to alert all 500 ticket holders by text message. You could pick up your phone and send 500 messages by hand — or you could integrate an SMS API like **Callr** that sends them automatically, using exactly the principles above. The result is a sharp gain in efficiency and the ability to build workflows that add real value to your business. ## Webhooks and the "Hollywood principle" When a program uses an API, it makes a request — often described as "calling the API." Each call consumes server resources, which is why many commercial APIs cap how many requests you can make in a given window, so their systems don't get overloaded. In some situations, constantly calling an API just to check whether something has changed is wasteful. It would be far more efficient if the API could simply tell you the moment new information arrives. That is exactly what webhooks do. Picture a retail website that has integrated a payment provider's API so customers can buy easily. Important events happen on the provider's side that won't show up unless you ask — for example, when a subscription payment fails. Polling the API over and over to check is an inefficient use of resources. But if your site never learns the payment failed, you end up with unhappy customers. **Webhooks solve this by reversing the flow.** Instead of your program repeatedly asking the API for updates, the API notifies your program the instant a pre-defined event occurs. This is sometimes called the **"Hollywood principle": don't call us, we'll call you.** For a payment provider, webhooks can update a customer's record when a payment succeeds or fails, flag a dispute, and so on. At Callr, we use webhooks the same way — to tell our clients when a text message has been delivered, when an account balance is running low, and for many other events worth knowing about the moment they happen. ## Webhooks in action To pull these ideas together, here is one last example of an efficient, automated workflow. Imagine you are a sales rep at a trade show, logging the prospects you meet on a tablet. Your team uses one tool to collect contact details from a form and another to manage leads on a shared board. Prospecting at a show is exhausting, and the last thing anyone wants to do is hand-copy each lead's details, do some online research, and assemble a card for every person they talk to. This is where a no-code automation tool comes in — the kind that connects different APIs into smarter workflows without you writing any code. With it, you could: - Use a webhook so that the moment someone fills out your contact form, a new lead card is created on your shared board automatically. - Go further by adding a data-enrichment service that takes an email address and pulls back relevant public information about that person or company. Wire those together and, each time your rep enters a prospect's email, a pre-populated card appears on the board for the whole team to see — complete with the form notes and the enriched details — with no extra effort from the rep. That is a remarkably easy way to put APIs to work and streamline a workflow, without a single line of code. ## Key takeaways A few things worth remembering: - An **API** is an **I**nterface used by **P**rograms to interact with an **A**pplication. - APIs **expose** data; developers write programs that **consume** them. - Mapping providers, social platforms, payment processors, and messaging services like Callr all offer useful APIs — almost every modern service does. - Developers **plug** these APIs into their own applications instead of reinventing the wheel, which frees them to focus on the core value of what they are building. - APIs are designed to expose data in a **machine-readable** format (often JSON), whereas websites expose data in a **human-readable** format (images, links, forms). - **Webhooks** are reversed API calls: the request is sent by the external service and received by your application, the moment something happens. This guide focused mainly on web APIs, but many other types of API exist. If you want to see one up close, take a look at Callr's API documentation — Callr ships a REST API and webhooks you can put to work right away. --- # Turn Call Data Into Sales: A Practical Guide to Optimization *2025-06-10 · Callr* Every customer call carries data you can act on. Here's how to use call tracking and analysis to find better leads, personalize selling, and grow revenue. What if every customer call were an opportunity you could measure? Many businesses field hundreds, sometimes thousands, of calls a day, yet few extract real value from them. Each conversation holds information that can sharpen your understanding of customers, refine your sales strategy, and lift revenue. Despite the rise of chat, email, and messaging, the phone still matters at decisive moments in the customer journey. A call is a real, human exchange — direct, high-intent, and often the point where a deal is won or lost. The trick is to treat the data inside those calls as an asset rather than letting it disappear. Here is how to turn call data into concrete opportunities to grow your business. ## What call tracking is and how it works Call tracking captures and analyzes inbound calls so you can attribute them to a source. The mechanism is simple: you assign unique phone numbers to specific campaigns, channels, or landing pages. When a call comes in on a given number, you know exactly which marketing effort drove it. From there, you can see which sources produce the most calls and the most sales, and direct your budget accordingly. A simple example: a cleaning-services company advertises on both search and social. Call tracking reveals that its most profitable calls come from search ads. With that evidence, it shifts more budget to the channel that actually converts. In short, call tracking replaces guesswork with attribution, so you can make the most of every customer interaction. A large share of business exchanges still happen over the phone, and many companies report that phone leads convert better than form fills or email inquiries. That is precisely why call tracking belongs in your measurement stack rather than as an afterthought. ### The cost of not tracking calls The flip side is just as telling. Missed and mishandled calls are lost revenue — every unanswered call is a prospect who may not call back. Many organizations also never connect their inbound calls to the campaigns that generated them, which leaves a blind spot in their marketing ROI. Call tracking closes that gap: it lets you capture, analyze, and improve call handling so fewer potential customers slip through. ## Why calls matter for sales A phone call is often the first direct contact between a company and a customer, and it is dense with useful signal: - **Explicit and implicit needs:** What problem is the caller describing? Which products or services are they genuinely interested in? - **Tone and emotion:** Are they enthusiastic, hesitant, or frustrated? That cue can shape how a rep responds and whether the conversation moves forward. - **Recurring patterns:** Which keywords and questions come up again and again? When many callers raise the same concern, it often points to something to fix in your offer or your messaging. Read these signals well and you understand customer expectations more clearly — and you surface opportunities to improve and sell more. For instance, a car dealership might notice that callers sound uncertain whenever financing comes up. By coaching the team to explain options calmly and answer common concerns up front, the dealership builds confidence and improves its conversion rate. ### How to put call data to work #### 1. Use the right analysis tools Modern telephony can analyze calls as they happen. With a platform like Callr, you can: - Automatically transcribe calls into searchable text. - Surface common keywords — products, objections, frequent questions. - Gauge sentiment and satisfaction so you can adjust your approach. That gives sales teams the context to adapt quickly instead of relying on memory or notes. #### 2. Personalize the sales approach Customers want to be heard and understood, not treated as a number. Call data lets you segment profiles and tailor what you offer to each customer's real needs. You can time follow-ups around what a prospect is likely to need next, and refine how your team handles recurring objections. The more relevant your approach, the higher your odds of closing. #### 3. Measure results and keep improving A sound strategy rests on clear, measurable indicators. With call data, you can track KPIs such as: - **Conversion rate per call:** how many calls lead to a sale. - **Duration of successful calls:** whether shorter or longer conversations convert better. - **Campaign ROI:** which campaigns generate the most valuable calls. With these numbers in hand, you can adjust your strategy and improve sales performance over time. The payoff is threefold. Used well, call data boosts sales by pinpointing high-potential opportunities, makes sales teams more efficient by giving them precise context on each prospect, and strengthens customer relationships through a more personal approach. ## Conclusion Call data is a genuine opportunity to grow revenue. With Callr, you can turn every phone conversation into a rich source of insight and sharpen how you sell. Ready to make the most of your calls? Every missed one could be a sale left on the table. Learn how Callr can help your business at [callr.com](https://www.callr.com/en). ### Further reading For more on attribution, see our article on using call tracking to calculate ROI for offline campaigns — it covers how businesses can measure the return on investment of their advertising in detail. --- # Better Customer Experience with AI Agents, SMS, and IVR *2025-05-27 · Callr* How AI agents, SMS automation, and modern IVR work together to deliver faster, more personal customer experiences across voice and messaging. Automating customer conversations is no longer a novelty — it's an expectation. Customers want fast answers at any hour, on the channel they already use, without waiting on hold or repeating themselves. The good news for businesses is that the building blocks are mature and proven: AI agents for messaging, smart IVR for voice, and SMS for reach. Used well, they reduce effort for your customers and free your team to focus on the conversations that actually need a human. Below we walk through where each one fits, how a typical flow works, and what it takes to get value from them. ## AI agents for customer support Customer support is one of the most reliable places to deploy an AI agent. It works for both sides of the conversation. For your customers, an AI agent means help is available around the clock, with near-instant answers — and no hesitation about "bothering" someone with a basic question. For your team, it means the routine, repetitive requests get handled automatically so live agents can spend their time where it counts. A few reasons AI agents have become a standard part of support: - **Fast and efficient.** They handle common tasks — tracking an order, booking an appointment, surfacing the right help article — in seconds, at any time of day or night. - **Personalized.** With access to customer data, an AI agent can greet people by name and tailor its responses to their account, history, and context. - **Interactive.** Unlike a static FAQ page, an AI agent responds to what the customer actually asks, creating a back-and-forth that feels closer to a real conversation. On the business side, an AI agent reduces the load on live agents rather than replacing them. It improves how you allocate your team's time, sharpens the analytics your support function collects, and — because it slots into the channels you already run, from your help center to direct messaging — it's easier for customers to adopt. ### What a support flow looks like Here's a simplified ticket flow when an AI agent handles the first line of support: 1. **The customer opens a ticket.** Someone hits a problem with your product or service and starts a conversation with the AI agent in your help center or messaging channel. 2. **Topic detection.** Using natural language understanding, the AI agent recognizes the subject of the request and tags the ticket with a high-level category — delivery, payment, account error, and so on. 3. **Immediate assistance.** If the issue is a common one, the AI agent answers directly or points the customer to the right resources in your help center. 4. **Follow-up.** Through guided questions, the AI agent checks whether the resources solved the problem or whether the customer needs more help. 5. **Escalation (when needed).** Before handing off to a person, the AI agent collects what the human agent will need — details about the customer's setup, a clear description of the issue, relevant context. 6. **Human response (when needed).** A live agent takes over with the ticket already tagged and the full conversation in front of them, so they can size up the problem fast and respond accurately. ### Requirements and limits This flow works well, but it isn't free. To build a support AI agent that performs, you generally need a sizeable base of past tickets to learn from and a high degree of repetition in the questions customers ask. That makes it a natural fit for **B2C businesses with large user bases**. Even when those conditions are met, it takes a real budget and the right technical skills on your team to build and maintain. ## Voice automation with IVR You've heard it before: "Press 1 for support, press 2 for billing." That's IVR — Interactive Voice Response. It's sometimes dismissed as outdated, but modern IVR is far smarter and more usable than the menus of a decade ago. IVR is often a better fit than a messaging AI agent for businesses with smaller, more specialized customer bases — many B2B companies, for instance, where each client has a highly customized setup that's hard to categorize automatically. Plenty of companies also still take support requests and sales inquiries the way customers prefer: over the phone. To handle that flow of inbound calls efficiently, IVR combined with automation is the right tool. IVR lets callers interact with your phone lines using speech recognition or their keypad, responding with prompts that guide them to the right place. It's a practical way to: - **Collect information** about each caller before they reach an agent. - **Prioritize calls by value** — for example, cutting or eliminating the wait for high-value customers. - **Route calls** to the agent best suited to handle them. ## A closer look at SMS We tend to picture automated messaging inside OTT apps like WhatsApp, Messenger, or Telegram. But SMS has a decisive advantage: reach. It's one of the most universal communication channels there is, and unlike app-based messaging it works on any phone — including the most basic handsets, with no internet connection required. That's the real benefit of SMS automation: it brings smart, interactive services to every customer, regardless of device. ### Going further with two-way notifications SMS is excellent for keeping customers updated — order status, delivery alerts, and the like. Messages get read fast: the vast majority are opened within minutes. But a one-way notification can frustrate the recipient when they need to act on it. With an interactive SMS flow, you can turn a notification into a short, useful exchange. Take a delivery confirmation: > Your package will be delivered tomorrow between 2 PM and 4 PM. > > Reply "OK" to confirm, or "Reschedule" to pick another time. If the customer replies "Reschedule," the automated flow can offer three alternative delivery windows and let them confirm by replying 1, 2, or 3. Because the interaction is tightly framed, it's straightforward to build — and the same pattern applies to appointment reminders, confirmations, and other short, structured exchanges. ## Bringing it together Improving customer experience doesn't have to be complicated. AI agents handle high-volume messaging, modern IVR manages inbound calls intelligently, and SMS reaches everyone with two-way interactions that customers actually respond to. Used together — and built on a reliable communications platform — they create smoother, more personal, and more efficient interactions across every channel your customers use. --- # SMS API & SaaS Integration: The FAQs, Answered *2025-05-13 · Callr* Thinking about adding an SMS API to your SaaS platform? Integration timelines, common pitfalls, data ownership, and A2P regulations, explained. An SMS API can add real value to a SaaS platform, but for founders, marketers, and sales teams it's not always obvious *when and how* to bring a new channel into your stack. What should you watch for? What needs to be in place first? And what might trip you up *before* you commit? To help you navigate the decision, our co-founders, Taoufik Zagdoud (CEO) and Florent Chauveau (CTO), worked through the questions that come up most often when SaaS teams are weighing an SMS integration. Taoufik has well over a decade in telecommunications, including roles at SFR, Afone, and IC Telecom. Florent is a full-stack engineer whose work spans hardware, networking, security, data modelling, APIs, and user experience. ## How long does it usually take to integrate an SMS API? **Florent:** It depends almost entirely on how complex the workflow is. Some cases are simple: you want to fire off an SMS when someone signs up. Others are involved, like sending a personalized reminder when a customer misses a monthly payment, which means pulling data from your billing system, merging variables from your CRM, and then routing the message through your CPaaS provider. For a straightforward scenario against a clean REST API, you could be live in a few hours. A genuinely complex workflow with many moving parts can take months of development. Be honest with yourself about which one you're building. ## What if you're a small SaaS startup without the internal resources for a complex integration? **Florent:** The most practical option is usually to bring in a freelance developer. They can review your documentation, work directly against the REST API, and get the integration shipped without you having to staff it long-term. ## What problems come up most often during integration, and how do you avoid them? **Florent:** Two recurring issues stand out. The first is fit: trouble appears when the workflow is more complex than the team expected, or when an existing IT system isn't built to support it. The second is volume. Think carefully about how many requests you'll send to the CPaaS API and how long that takes. Say you want to send 5,000 messages built from CRM and billing data. If your own systems can't handle that throughput, you risk overloading your servers, and you may not even see delivery confirmations come back on your DLR report. The fix is unglamorous but reliable: talk to your CTO about capacity planning and sizing, and agree on the workflow with your tech team up front so your infrastructure can absorb the new load. ## Who is responsible for securing the data that flows through these messages, the SaaS provider or the SMS API provider? **Taoufik:** The data lives with the SaaS provider, and that's where it stays. A good SMS API provider doesn't analyze, repurpose, or monetize that data. At Callr, we don't sell customer data, and frankly, anyone who does is making a serious mistake. Bear in mind that some sectors carry strict privacy rules, like HIPAA in the United States for health data. Know which regulations apply to you and do your due diligence before you send a single message. ## How do you know whether your SaaS customers would benefit from SMS? **Taoufik:** SaaS providers tend to see the most value from SMS through transactional notifications, especially if they don't already have a mobile app. The whole point of a transactional alert is that it gets read quickly, and SMS is delivered almost instantly and works across every device. It reaches people anywhere in the world, regardless of internet access or the kind of phone they carry. SMS is also strong for tightening up customer relationships. Sending an appointment reminder by text rather than a phone call removes needless inbound calls that tie up your lines and your team. If you run a service that handles personal care or appointment bookings, SMS is often the smart choice. ## When should you use SMS versus email, voice, or push notifications? **Taoufik:** It mostly comes down to timing and reach. If something needs to land in real time, choose SMS or push over email. If your users might be offline, travelling, haven't installed your app, or have opted out of push, SMS is the safer bet, since push notifications are easy for people to tune out. And when you need an absolutely reliable way to reach someone, say, in an emergency, use voice. Voice is the most personal and reassuring channel, and the easiest for people to act on. ## Are some countries stricter than others about A2P SMS? **Taoufik:** Yes, and the differences are significant. In France, for example, marketing messages are blocked after 10 pm on any day, all day Sunday, and on public holidays. Other markets go further: the United States, the United Arab Emirates, and several others require regulatory validation before a marketing campaign can go out. Make sure you and your users understand the rules in each country you send to, and be especially clear on the line between marketing and alerting. ## Key takeaways - Before building your SMS workflow, talk to your CTO about capacity planning and sizing. - The more complex the workflow, the longer the integration. - SaaS providers own and are responsible for their users' data security. - SMS works particularly well for transactional notifications and customer-relationship workflows, thanks to its immediacy and deliverability. - SMS regulations differ by country, so do your due diligence, especially around marketing versus alerting, permitted sending hours, content restrictions, and opt-out handling. --- # Fighting Robocalls: What ARCEP Decision 0881 Means for Telecom Professionals *2025-04-29 · Callr* How ARCEP Decision 0881 reshaped caller ID rules and automated calling in France, and what it means for contact centers and telecom operators. Phone numbers are a shared resource, and like any shared resource they are easy to over-use and hard to govern. France's telecom regulator, ARCEP, took on exactly that problem with Decision 0881: a sweeping update to the national numbering plan that also tightened the rules around automated calls and text messages. If you run a contact center, send voice or SMS campaigns, or operate a network, the decision changes the ground you stand on. Here is a clear-headed look at what it does and why it matters. ## Managing a common good In telecommunications, providers constantly share standardized resources: phone numbers, URLs, IP addresses. When everyone optimizes for their own short-term gain, the resource degrades for the whole group, including the people exploiting it. Economists call this the Tragedy of the Commons, and the numbering plan is a textbook example. The framework that governed French numbering had aged badly. ARCEP set out two goals with Decision 0881: foster innovation and new uses, and improve how the scarcity of numbering resources is managed. > ARCEP is the French regulator for electronic communications and postal services. Like the FCC in the United States, its job is to regulate the market and keep competition fair among providers and other players. The decision tackles looming number shortages in some regions and adds restrictions on geographic numbers. But it goes well beyond a numbering update: it also introduces new protections for end users, and corresponding obligations for businesses, against automated calls and messages. A few facts set the scene: - The previous framework dated back to 2001 and 2005, and no longer fit how networks were used. - Demand for numbers kept rising, driven in part by machine-to-machine (M2M) traffic. - It was technically possible, and too easy, for businesses to conceal the caller's identity on automated calls. ## 1. The two sides of a call Regulating telecommunications is a balancing act. The regulator has to reconcile what businesses need with what citizens and customers expect, and the two pull in different directions. Businesses are also better organized and better funded, which gives them more weight with regulators. The tension is real, and businesses sometimes have to be protected from themselves. Without any guardrails, the market drifts toward another tragedy of the commons: companies flood the network with automated calls and texts until people do whatever it takes to escape the noise, from call-blocking apps to swapping numbers to abandoning voice and SMS altogether. Rather than framing businesses and citizens as opponents, it is more useful to find the overlap. In telecom, their interests are aligned up to a point, and that shared middle ground is where good regulation lives. ### Don't forget the third party: operators There is a third side to every call: the operators. They have commercial relationships with both end users and the businesses that use their network, legitimately or otherwise. Since operators earn on both sides, it is tempting to assume they have little incentive to fight robocalls. In reality, operators have to manage shared infrastructure like a scale: excess on one side eventually drives excess on the other. ### 1-A. Innovation that serves businesses Often, what businesses want and what consumers want line up. Automation is a good example. - **For consumers**, well-built automated support means faster answers, available any time of day or week, and sometimes the relief of not having to talk to a person at all. Done right, automation does not replace human agents; it frees them to handle the edge cases where they are genuinely needed. - **For businesses**, automation brings consistency. Every interaction follows a defined path, which matters enormously for brands that care about their image, and because it happens on a digital channel it becomes traceable and measurable end to end. The detail is where things go wrong. Some companies treat automation purely as a way to cut headcount and minimize support costs. That approach is common, and it usually damages both brand perception and customer satisfaction. And so far we have only discussed inbound support. The full picture also includes outbound campaigns, which is where most consumer frustration concentrates. ### 1-B. Rage against the machine? For consumers, automation feels very different depending on direction. Inbound automation, where the user reaches out to a service, is usually welcome: it improves accessibility and typically sits alongside human support. #### "Human!" Even in that best case, frustration shows up. People learn tricks to escape rigid systems: shouting "agent" or "human" at an IVR, pressing 0, hammering the pound key, anything to reach a person better able to help. Entire resources now exist to help callers find a company's number and bypass the menu to a live agent. #### Outbound campaigns (robocalls) Outbound automated calls and texts drive the bulk of end-user frustration. The techniques have multiplied: recorded-voice calls, SMS blasts, ringless voicemail. As the cost of a minute or a message kept falling, the conditions for a flood of automated activity were perfect. A handful of tactics concentrate the anger: - **Flash calling**: ringing a number once so the recipient calls back. - **Obfuscation**: making a call look local when it actually originates abroad (more on this below). - **Repetition**: once a number enters a database, it tends to be shared widely. Some people receive five to ten automated contacts a day, and even carriers themselves are guilty of the practice. ### 1-C. Do we still need phone numbers? One more piece of context. Communication has changed fast. Over-the-top (OTT) messaging apps, which carry conversations directly over the internet and bypass operators, have grown enormously in both users and usage. > OTT messaging apps let people communicate directly over the internet, bypassing telecom providers. Some of these apps are still tied to a phone number; others identify users by email or username. On top of one-to-one messaging, community platforms like Discord and Slack have become primary channels for large groups. Living without a phone number used to be impractical. It is now entirely workable, and for younger generations it is the norm: they keep a mobile plan, but most of their usage is data-based, and they rarely need to share a number at all. There are now plenty of ways to chat, call, or video-call anyone in your network. With that context in place, we can look at the decision itself. ## 2. Decision 0881 at a glance Decision 0881 is a large package; the original document runs well over 100 pages. If you operate a contact center or run automated voice or text campaigns in France, it is worth reading in full. Rather than covering every item, we will focus on the decisions that capture the spirit of the text. ### 2-A. A tighter framework around caller and sender identity > Caller Line Identification (CLI), or Sender ID, is the number or string shown on the recipient's phone. Businesses used several tricks to mislead recipients by spoofing it, most commonly displaying a local number to lift pick-up rates even when calling from abroad. The decision (Article 7.4) gives a precise definition of a "modified" caller ID: > The caller line identifier is considered modified when the number displayed on the end user's phone cannot be used to call the caller back. It then sets conditions to regulate the practice. The two most significant and novel ones: 1. **Two-way requirement**: if you use a number to call or text a prospect, that prospect must be able to reach you back on the same number for as long as the campaign runs. 2. **Territoriality**: when using geographic or non-geographic numbers (for example French mobiles 06/07 or geographic 01–05 numbers), the caller must be able to guarantee the agent is genuinely calling from France (Art. 7.4.2.b). ### 2-B. A new way to regulate automated calls and texts ARCEP (Article 7.5) lists the main nuisances tied to automated campaigns and sets a framework to govern them. #### Restrictions on automated communications The section is dense, so here are the points that matter most: 1. Automated dialers are explicitly named in ARCEP's list of nuisances, though their precise legal status remained unclear even after we asked the regulator directly. 2. New rules limit which number types may be used for automated campaigns and impose transparency on the caller. Automated systems can no longer use "territorialized" numbers (with the exceptions below). 3. Three core limitations are defined, and they reveal what kind of automated traffic ARCEP considers beneficial on the network. "Territorialized" numbers include: - **Geographic numbers**: 0[1–5] XX XX XX XX in France. - **Mobile numbers**: 06/07 XX XX XX XX. - **Non-geographic numbers** (distinct from mobiles): 09 XX XX XX XX, not tied to a region. As a result, automated traffic is by default confined to one number type: long virtual mobile numbers, used mainly for automated and machine communications, including M2M. The three exceptions: 1. **Small scale**: systems calling or texting five distinct numbers or fewer. 2. **Balanced texting**: automated SMS systems that receive as many texts as they send, or more. 3. **Balanced calling**: automated calling systems that receive significantly more calls than they place. #### The traffic ARCEP wants to encourage Here ARCEP introduces a useful principle: automated communication should be balanced between inbound and outbound. The logic holds up. Why throttle a high-volume service that users voluntarily reach out to? A very low inbound-to-outbound ratio, on the other hand, is a reliable signal of spam. Notably, the balance test is more lenient for text than for voice, which reflects ARCEP's intent to support helpful automated messaging while cracking down on robocalls. > The decision is explicit that calls placed manually by agents, without an automated dialing system, are not treated as emitted by automated systems (Decision 0881, footnote 33). The principle has clear limits, though. Two cases illustrate the problem: 1. **Critical alerting**: a seismic monitoring system that warns local populations of a life-threatening event generates intense outbound traffic over a short window. It breaks the balance principle while literally saving lives. 2. **Debt collection**: this work is mostly outbound by nature, since reaching a debtor often takes several attempts. The principle could brand a legitimate service as illegitimate. ### 2-C. Enabling new uses ARCEP also made several moves to support innovation: - Make it easier to use multiple numbers on one device, so a single subscription could carry both a personal and a professional number routed to the same line. - Allow SMS and MMS on geographic numbers, which had been restricted to non-geographic numbers in France. - Make it easier to use long virtual numbers for IoT devices, including for users outside France. > Decision 0881 was adopted in July 2018, with the changes to automated calling slated to take effect in August 2019 to give providers time to adapt. With the substance clear, here is how it plays out for the industry. ## 3. An insider's view: a conversation with Callr's CEO Reading a new regulation is one thing; understanding its real impact is another, and that is where industry experts earn their keep. We sat down with Taoufik Zagdoud, CEO of Callr, the French smart voice services provider operating since 2009, to talk through Decision 0881 and its consequences. ### What was your first reaction to Decision 0881? **Taoufik Zagdoud**: As a VoIP carrier, our position is interesting. Legacy carriers have historically resisted extra regulation because they see it as a business risk. Our view is more balanced. We recognize that a strong legal framework is both necessary and good for the future of the industry. We also invest heavily in our customer relationships so we can share what we know and help them adapt. The best practices are well documented; what we still need is to convince businesses that preserving mobile as a high-quality, responsive medium is in their own interest. We regularly publish guidance to push adoption of those practices. There is no reliable way to filter traffic in advance without treating everyone as a suspect, so we work the other way around. We monitor our network closely and make it as easy as possible to report abuse, through a dedicated channel: abuse@callr.com. ### Will it be enough to contain spam and abuse on the networks? **TZ**: My experience tells me it won't be enough on its own, but it is still a necessary step. The text defines and regulates concepts and technologies that were living in a legal grey area, and it is forward-looking, paving the way for new uses such as dedicated ranges for machine-to-machine traffic. That said, neither the form nor the substance fully solves the problem, and here is why: 1. **Wishful thinking.** Setting a principle to ban a practice is easy. Enforcing it is not. Regulators tend to assume technology can bridge principle and implementation, and here that is unrealistic. What even counts as "automated traffic," and how do you detect it automatically? With telecom virtualization, you essentially cannot. There are so many ways to spoof identity or disguise automated traffic as human-initiated that any technical control will be highly game-able, and gamed. 2. **Automation is not the enemy.** The decision reads as if automation were inherently bad. Plenty of automated use cases provide real, sometimes time-critical value: emergency alerting, non-profits helping homeless people find food, informational services. 3. **Real-world consequences.** Most call centers serving developed markets are set up in lower-wage neighboring regions. They serve major banks, insurers, and telecom providers, so changes to telecom rules have a tangible effect on jobs in those countries. Even in a magical world where you could block all automated calls, demand for human agents would rise, pushing operators to chase ever-lower costs elsewhere. That race to the bottom is not a good outcome. ### How is the industry reacting to the crackdown on automated calls and texts? **TZ**: Among peers I hear real concern about the future of automated campaigns and contact center work. A crackdown on predictive dialing, if enforced, would have a major impact, and some go as far as saying it could jeopardize the whole sector. I don't share that view. It reminds me of the pre-GDPR panic: enormous expectations and worry about what would happen, followed by a far more moderate reality. With GDPR, many businesses found exemptions, and even those who couldn't were not especially worried, because enforcement in the first year was very limited relative to the number of reported violations. Since GDPR alone did not curb phone harassment, ARCEP added the restriction that mobile CLIs (06 or 07) can no longer be used for automated campaigns. The pattern repeats elsewhere; the US has stiff robocall penalties on paper, but collection of those fines has lagged far behind. The bigger pressure may come from consumer advocacy. The fear of a public backlash led by consumer groups can do more to clean up practices than the letter of the law. France's La Quadrature du Net launched legal action against several large tech companies the day GDPR took effect, backed by thousands of citizens, and it produced results, including a substantial CNIL fine. GDPR's biggest merit, in my view, was reminding consumers they have rights over their data and can assert them. > La Quadrature du Net is a French NGO that defends users' privacy online. ### How do you account for regulation when you design new Callr services across different legal frameworks? **TZ**: We have offices in France and the US, so we follow both ARCEP and the FCC closely, and since we serve customers worldwide we track major changes from many countries. When we built our voice and text campaign tooling, we drew on FCC and FTC rules, and we generally aim to exceed the legal minimum. For example, we handle STOP messages at the platform level, so the feature is available in every country we serve, even where it is not legally required. SMS traffic tends to be more tightly regulated and better enforced than voice. Several countries impose strict rules on text, including the United Arab Emirates, where shortcode use and campaign content must be approved in advance, and China, where routes are cut when spam is detected. As a rule of thumb, where authorities respond swiftly and forcefully against the operator, practices improve quickly, because operators themselves filter the unwanted traffic. The voice-versus-text gap comes down to the nature of the traffic. Text is easier to analyze automatically, which simplifies spam detection, and the widespread STOP mechanism makes abusive behavior easy to spot when a company keeps contacting people who opted out. That is why flagging systems are easier to build and maintain for text. ### France isn't alone. What approaches do other countries use, and what works? **TZ**: Over a decade in the field, I have seen two approaches deliver meaningful results. The first, used in the United States, combines stronger laws, heavier enforcement, and larger fines. Tightening all three at once made a real dent in abusive and misleading calling. The second is simpler and more direct: automated calls and texts proliferate because they are cheap, so some countries raised voice and SMS prices to make them less attractive. Rates can be raised further on inbound international calls to limit foreign call centers' ability to dial in. This worked well in parts of Europe, notably Switzerland, Belgium, and Italy. More radical models exist too. In the United Arab Emirates, marketing campaigns must be declared in advance to the regulator, and the operator is held directly responsible for any unlawful traffic on its network. That forces operators to be careful about what they carry, and it has measurably reduced abuse. Emirati operators now offer extensive resources to help business customers comply. ## References and further reading For a deeper look at the decision and the broader robocall problem: - ARCEP draft decision for public consultation on relaxing geographic restrictions for 01–05 numbers and increasing user protection (April 2019). - "The Source of Robocalls," Om Malik's blog (April 2019). In French: - Décision n° 2018-0881 du 24 juillet 2018 de l'ARCEP établissant le plan national de numérotation et ses règles de gestion (Légifrance, July 2018). - "La réglementation de la numérotation change profondément," Frédéric Foster, Lexing (September 2018). --- # Bloctel Explained: The French Do-Not-Call List for Businesses and Consumers *2025-04-15 · Callr* How Bloctel, France's official do-not-call registry, works for businesses cleaning prospecting lists and for consumers blocking unwanted calls. If you make outbound calls in France, or you simply want fewer of them, Bloctel is the rule that shapes both sides of the conversation. It is France's official do-not-call registry: free for consumers who want to opt out of unsolicited sales calls, and mandatory for any company that runs cold-calling campaigns. Here is how it works, what it covers, what it doesn't, and why respecting it is good for everyone who relies on the phone as a channel. ## What is the Bloctel do-not-call registry? Bloctel is the French do-not-call list. It lets consumers block unwanted commercial calls to their personal numbers, free of charge, under French law. In return, businesses are required to clean their prospecting lists against the registry before calling, so that people who have opted out are left alone. In principle that might sound like a consumer can shut out every salesperson, marketer, debt collector, or campaigner who picks up the phone. In practice there are clear exceptions. A registered number can still legally be called when: 1. There is a **current contractual relationship** between the consumer and the business. 2. The call concerns the **sale of newspapers, periodicals, or magazines** (subscriptions to the press). 3. The caller is a **public-sector body, a polling institute, or a non-profit organization**. 4. The consumer **freely and unambiguously gave the business their number** with the intent of being contacted. ## How does Bloctel work? ### For businesses If you run cold-calling campaigns, it is your responsibility to make sure you are not calling consumers who have registered their numbers on Bloctel, unless you fall under one of the exceptions above. That obligation holds whether your own team does the calling or you outsource it to a third party. You also cannot rent or sell lists that contain Bloctel-registered numbers to anyone else. One detail catches a lot of companies out: even if you hire a third party to clean your prospecting lists, the Bloctel account must be registered in **your** name and paid for by you. The compliance responsibility stays with you, not your provider. ### How do I avoid calling numbers on the Bloctel list? Opposetel, the operator appointed to run the registry, is responsible for cleaning companies' calling lists against Bloctel. The service is paid, on a subscription basis. Every business must run its list through Opposetel **before each cold-calling campaign**, before handing a calling list to another company, and at least once a month for any campaign that runs longer than 30 days. Setting up a professional account with Opposetel follows these steps: 1. **Pre-register on Bloctel** - Complete the form with your company details on the official Bloctel site. - You receive a confirmation email and a username for your account. 2. **Test the service** - Trial the Opposetel service, read the FAQs, and contact the support line if needed. 3. **Choose your subscription** - Pick the plan that fits your volume and select a payment method. - Once payment clears, Opposetel confirms that your subscription is active. 4. **Configure your users** - You can set up several distinct users; give each one a username. - Make sure every user is aware of the applicable terms and conditions. 5. **Submit your calling lists** - You receive a confirmation email when a list is uploaded. - You download the cleaned files once they have been processed. Opposetel processes files in the order they arrive. Outside of unusually busy periods, you can expect a cleaned prospecting list back within about 72 working hours. ### For consumers If you live in France and want to stop unsolicited sales calls, you can add your number to Bloctel: 1. Complete the form on the Bloctel website with your name, email, address, and the numbers you want listed (up to eight). You also create an account during this step. 2. Validate your request. Bloctel sends a confirmation email within about 48 hours. You have 10 days to click the validation link, otherwise the request expires and you start over. 3. Bloctel sends a second email with a confirmation number, which gives you access to the account you created in step one. From there you can update your details or report illegal calls. Your numbers are protected from unsolicited commercial calls within 30 days of validation at the latest. Registration lasts three years, and you can cancel at any time. ## What Bloctel does not cover: scams, robocalls, and text messages Registering on Bloctel does not block every nuisance. It only protects consumers from commercial calls placed by a business. For everything else, here is what to do. ### Automated and pre-recorded calls (robocalls) Automated, pre-recorded calls are legal **only** when you have given clear, unambiguous consent for your number to be used that way, for example by ticking a box. If you believe your number is being called illegally and you know which company is responsible, you can file a complaint with the **CNIL** (Commission Nationale de l'Informatique et des Libertés), France's independent data-protection authority. Companies that break the rules can be fined per illegal call. ### Scams If you are getting calls designed to harvest your personal information for fraud, you can report the caller to the CNIL when you can identify them, and you can also file a criminal complaint with the police or public prosecutor. ### Voicemail traps Bloctel does not block voicemails that try to lure you into calling back a premium-rate number. The safest move is not to call back. Report the offending number by texting it to **33700** (free of charge) with the message `SPAM VOCAL 0X XX XX XX XX`. You will get a confirmation that your report has been forwarded to the relevant carriers. ### Unsolicited SMS or MMS Bloctel does not cover unwanted text messages either. To stop them: - Reply **STOP** by SMS to the number that texted you. The company is legally required to confirm your request and remove you from its database. Texting **CONTACT** to the same number returns the sender's customer-service details. - Forward the message to **33700** (with no added comment) so carriers can act directly against the sender. The service works across all French operators and is free on most networks. Numbers flagged through 33700 can be reviewed by the **DGCCRF** (France's consumer-protection and fraud authority), which can pursue legal action. - You can also report the sender to the CNIL, the police, or the public prosecutor. ## Why respecting Bloctel matters If you are reading this as a business, you might see Bloctel as a constraint on prospecting and growth. It does limit who you can cold call, but that is not a bad thing. Anyone using the phone to reach customers, whether a sales team or a contact center, has an interest in treating the channel with respect. That means applying real targeting, personalization, and judgment instead of dialing through a raw list. When people feel harassed, they stop answering numbers they don't recognize, let calls go to voicemail, and file complaints. That damages your standing with carriers and erodes trust in the phone for everyone. Rules like Bloctel, taken seriously, keep the telephone a credible and effective way to reach the public. Ignored, they push the whole channel toward irrelevance. For teams building compliant outbound and inbound voice flows, this is where good tooling helps. With Callr's REST API and webhooks, and low-code voice scenarios in Callr Actions, you can route, qualify, and connect calls intelligently, so the conversations that do happen are the ones people actually want. --- # The Why, What and How of GDPR for Telcos *2025-04-01 · Callr* A practical guide to GDPR for telecom businesses: why it exists, the rights it grants, the duties it imposes, and how to turn compliance into trust. Data protection is often treated as a burden. Even when the benefit to people is obvious, asking businesses to comply with one more set of rules can feel like friction. But the internet only stays a safe place to communicate when there are clear, enforceable rules behind it. The point of the General Data Protection Regulation (GDPR) is not only to protect individuals and curb abuse — it sets a single, workable framework for how personal data is collected and handled across Europe. When that framework works, everyone gains: people get real control over their data, and businesses operate in a more predictable environment with more trust from their customers. ## The challenge of data privacy online For years, the absence of strong, consistent data-protection rules had real costs — for individuals and for society. Telecom operators sit at the center of this, because they carry millions of sensitive conversations, messages, and call records. Without clear protections, people effectively lost control of their data: they couldn't tell who held it, what was stored, which data points were accessed, or why. When something went wrong, recourse was difficult or impossible. That gap let a wide range of intrusive but effective practices flourish — unclear wording, needlessly long terms and conditions, and controversial clauses buried in the fine print. GDPR makes many of these practices unlawful. ## Why individuals need a firm framework The societal stakes are higher than they first appear. Weak data rules erode privacy over time and concentrate influence in the hands of whoever holds the largest datasets. A reliable data-protection framework is, in plain terms, part of the infrastructure of a healthy democracy. The right to privacy is foundational: without it, freedom of expression and the ability to make free, informed decisions are all weakened. ## Why businesses benefit too Insufficient data rules hurt businesses as much as consumers. The biggest problem with the pre-GDPR landscape was fragmentation. Even within the EU, telecom and internet obligations differed from country to country, and that patchwork made full compliance genuinely hard. The more authorities a company had to deal with, the harder it became to be proactive about data practices. The old penalties made things worse. When fines are trivial next to the revenue at stake, they invite the "how much would it cost us to just pay the fine?" calculation — a sign that the legal system has failed to do its job. ## Cutting through the local regulatory jungle The flaws in the old framework are clear, but enforcement is the real test. A law has to be simple and clear enough to apply. When it isn't, the outcome looks much the same regardless of the policy on paper: - **Insufficient or unenforced laws** — countries where protections are weak, absent, or simply not applied. - **Permissive laws with little effect** — rules so lax that their practical impact is close to zero. - **Strong laws, weak enforcement** — countries with serious regulations on the books, but limited follow-through, so businesses incorporated elsewhere could do largely as they pleased. European telecom rules were a good example of how complicated this got. Requirements around shortcodes and phone numbers, SMS signaling and message priority (marketing versus notification), voicemail recordings, and contact-list management could differ significantly from one country to the next. ### The territoriality problem The biggest change GDPR introduced is extra-territorial applicability. Before it, the territorial scope of data law was ambiguous, and the core uncertainty was simple: **which law applies?** - The law of the business's country? - The law of the customer's country, if different? - Or the law of wherever the data was "processed"? For telcos this was a major risk, because many countries can be involved in a single data flow. Consider a call center: - located in **Tunisia**, - calling customers in **France**, **Italy**, and **Spain**, - on behalf of a company based in **Portugal**, - using a **German** software vendor to process the call data. Which law should that call center follow? GDPR makes the answer unambiguous: only the customer's location matters. Whether the company is European or not, and whether the processing happens inside or outside the EU, **any organization processing the personal data of people in the EU must comply with GDPR.** ## The three pillars of GDPR GDPR exists to give Europe a modern data-protection framework, fit for current and future needs. The previous EU directive on data protection dated back to 1995, so an update was overdue. The underlying principles carry over from that earlier directive, but the policies around them changed substantially. The most important changes fall into three groups: privacy by design, data ownership and control, and consent and penalties. ### I. Privacy by design The idea of privacy by design — building data protection into a product or service from the start, rather than bolting it on afterward — has been around for decades. In practice it means a system should collect only the data it actually needs (data minimization) and limit access to that data to the smallest number of people and services required to process it. Its inclusion in GDPR matters as much for what it signals as for what it mandates. In a world where every system followed this principle, much data-protection regulation would be unnecessary. A law won't change how companies think overnight, but it establishes the expectation. ### II. Data ownership and control GDPR gives people a new set of rights over how online services collect and process their data. These rights require real engineering work: businesses that handle customer data must offer a way for people to access, correct, and delete it. Large companies often had such interfaces already; smaller ones may need help from a provider to comply. #### Data portability Data portability means people can move their data easily from one service to another. Under GDPR, a person must be able to obtain the data they provided in a "commonly used and machine-readable format." This makes switching providers easier and lets people keep their own backups. It is a demanding requirement for telecom operators, who must adopt common standards so customers can move data between providers. In France, number portability has been the norm for telecom operators since 2007. Telcos, which collect, store, and analyze large volumes of customer data, have had to rethink significant parts of their processes — and in some cases find new revenue streams in the process. #### Right of access The right of access is a major step toward transparency. People can ask a data controller whether their personal data is being collected, where, and for what purpose. #### Right to be forgotten Already implemented in some countries before GDPR, this right lets a person: - erase their personal data, - stop further dissemination of that data, - and, in some cases, require third parties to halt processing of it. ### III. Greater responsibilities and bigger fines #### Gathering consent Consent rules were rewritten to reflect reality. Consent must now be given in an intelligible, easily accessible form, using clear and plain language — and it must be as easy to withdraw as it is to give. Together, these rules give people more control and make deliberately opaque terms and conditions unlawful. #### Penalties tied to revenue Penalties for non-compliance are much larger in both size and scope. For the most serious violations — such as ignoring privacy-by-design principles or failing to obtain consent — organizations can be fined up to **€20 million or 4% of annual global turnover, whichever is higher**, under a tiered system. New violations are also recognized, including failing to notify the authorities and affected individuals of a breach, or failing to carry out a proper impact assessment. #### Data protection officers Organizations that process data at large scale, or that handle sensitive data (such as medical or judicial records), must appoint a Data Protection Officer (DPO). The DPO is the main point of contact with data-protection authorities. They must be free of any duties that could create a conflict of interest, have the resources and skills to do the job, and report directly to the highest level of management. Breaches must now be logged internally and reported to the relevant authority. ## What GDPR means for businesses GDPR affects every organization that collects and processes personal data. Online services and social platforms are heavily impacted, but so is any company holding large customer files — telecom operators and marketing firms included. Below we look at the impact on telecom businesses, then point to broader ways to approach compliance. ### GDPR for telcos Telecom companies are meaningfully affected. Any business that moves information for warehousing, reporting, or marketing must be ready to delete or anonymize those datasets. Controllers processing data at large scale must appoint a DPO. Data portability obliges operators to provide customer data in a standard format. It can sound like a lot — but there's an upside. The framework is unified across Europe: complying with one set of rules is far simpler than tracking dozens of national regimes. Companies that already handle European customer data should work through a few essentials: - Ask new customers for explicit consent to collect and use their data. - Review existing customers' data, and remove anything that's no longer needed. - Train staff so compliance is continuous, not a one-off project. ### Compliance as an advantage Yes, getting compliant takes work in the short term. But that work is also an opportunity to adopt better data practices and run a cleaner, more efficient operation. Businesses that take privacy seriously and build trustworthy mechanisms earn the confidence and loyalty of their customers and prospects — which ultimately supports growth. Most would have needed to tidy up their data practices regardless. And as connected devices multiply and data volumes keep climbing, data minimization only becomes more important for keeping networks efficient. ## A note on the limits of GDPR No law is flawless, and GDPR is no exception. The rights it grants people are welcome, but the framework was designed around two assumptions: 1. that personal data of EU citizens sits in a small number of centralized locations, and 2. that identifiable organizations are responsible for implementing the standards. Decentralized, immutable systems sit in tension with both assumptions: their data is distributed across many nodes worldwide, and records generally cannot be altered once written. How regulation adapts to those architectures remains an open question. ## How Callr fits in Callr runs its own EU telecom infrastructure, with EU data residency by default — so the voice, SMS, and call-data flows you build through our REST API and webhooks stay on European footing from the start. That makes the data-minimization and locality questions above easier to answer. If you want the specifics on how Callr handles personal data, see our [GDPR page](/gdpr/), or [get in touch](/contact/) to talk through your use case. --- # Don't Kill Telephony: Why ASR and ACD Scores Matter *2025-03-18 · Callr* Two call-center metrics, ASR and ACD, reveal your traffic quality and keep carriers on your side. Here's how to read them and how to fix low scores. If you run outbound calling at any scale, two numbers tell you almost everything about the quality of your traffic: ASR and ACD. They are simple to calculate, but they carry real weight. Carriers watch them, regulators care about what they imply, and the long-term viability of telephony as a channel depends on keeping them healthy. Here is what each metric means, what counts as a good score, and what to do when yours slips. ## How do you calculate ASR and ACD? ASR (Answer-Seizure Ratio) is the percentage of attempted calls that connect successfully: **ASR % = (answered calls / total calls attempted) × 100** ACD (Average Call Duration) is the average length of the calls that do connect: **ACD = total duration of answered calls / number of answered calls** Some carriers call ACD "ALOC" (Average Length of Call) — same idea. Both are used to judge network quality, which is exactly why call centers need to track them and keep them in a sensible range. ## What counts as a "good" ASR and ACD? Scores that are too low signal poor-quality traffic flowing across the network. As a rough guide: | Metric | Excellent | Acceptable | Problematic | | --- | --- | --- | --- | | ASR | 60% or above | 40%–50% | Below 40% | | ACD | Over 6 minutes | 3–4 minutes | Under 1 minute | An ACD under a minute is a red flag worth investigating immediately. ## Do these numbers vary by country or industry? Yes. Geography matters, mostly because network quality differs from one region to the next. Industry and brand matter just as much. If you sell a complex product, or one with strong brand recognition, your ACD tends to run higher because people stay on the line. Other calls are simply less welcome: in France, tax-optimization offers and door-to-door-style phone or internet subscription pitches often see very low ACD, and pickup rates that barely register. ## What does a low ASR or ACD mean? In a call-center context, several distinct factors can drag these numbers down. ### Low ASR **Recipient behavior.** A low ASR often means large volumes of calls — frequently driven by dialers — are going out with nobody answering. The usual causes: contact lists are out of date (dead numbers), recipients recognize the traffic as unwanted and let it ring, or they simply aren't available (calling landlines during working hours). People who feel hounded by unsolicited calls also tend to take it out on the operator carrying the traffic. **Predictive dialer set too aggressive.** It is tempting to push dialers to maximum volume for a short-term productivity spike, but that backfires. Dial too slowly and agents sit idle. Dial too aggressively and a flood of calls gets cancelled because every agent is already busy — which tanks your ASR and eventually runs you into carrier limits. Aggressive predictive dialing is one of the most common reasons call centers see low ASR. Find the rhythm that balances idle agents against cancelled calls. **Busy lines.** A call that reaches a busy destination counts as a failed call. **Far-end switch congestion.** This tells you a center is placing too many calls to the same small area — one building, one small town — for the local switch to handle. ### Low ACD A low ACD (under three minutes) often means the person you reached doesn't see value in the conversation. But technical problems are just as likely to be at fault. **Audio quality.** Distant-sounding voices, echo, dropouts (from low-quality codecs, jitter, or packet loss), and stretches of dead air all push recipients to hang up fast. NAT and network-configuration problems frequently cause one-way audio, which also ends calls. And watch your bandwidth: every connection has a ceiling on the number of concurrent agents it can carry at good quality. Push past it and audio degrades for everyone. **Looping.** Repeatedly redialing the same wrong number drags your scores down for no return. ## Why do these metrics matter? Carriers dislike low ASR and ACD because the scores reflect badly on their network. Calls that go unanswered or end in seconds generate little revenue while still consuming resources, which creates friction between the carrier and the call center. Carriers can respond by blocking the worst offenders, raising prices, or shunting low-quality traffic onto dedicated channels. Keeping your scores reasonable keeps that relationship workable. Zoom out and the stakes are bigger. Marketing, polling, and outbound sales by phone only work as long as people actually pick up and listen. If call quality slides or people feel spammed, they sign up for do-not-call lists, complain to regulators, ignore unknown numbers, and let everything go to voicemail. Keeping the telephone experience reasonably pleasant is what keeps it a viable channel at all — degrade it far enough and you kill its value as a marketing, sales, or survey tool entirely. ## How do you fix a low ASR or ACD? 1. **Clean your data, before and after.** Before a campaign, run an HLR (Home Location Register) lookup to flag invalid mobile numbers before you ever dial them. After a campaign, prune your database by checking your CDRs (Call Detail Records) and removing numbers that never connected. 2. **Tune your predictive dialer to the productivity sweet spot.** Aim for the balance where an agent is almost always on a live call but prospects rarely answer to dead air. Your dialer vendor can help you calibrate this. 3. **Target better.** Call at times that suit your audience, and segment your list down to people genuinely likely to care about your offer. Campaigns that bother too many people will see ASR and ACD fall accordingly. --- # The Three Paths to VoIP: SIP Trunk, SIP Registrar, and IAX *2025-03-04 · Callr* Choosing a business VoIP setup? Compare SIP Trunk, SIP Registrar, and IAX across bandwidth, codecs, IP authentication, and NAT to pick the right fit. Whether you run a contact center or want to build telephony into your own product, business VoIP can feel like a maze. The setup that works for you depends on several factors at once: the quality of your internet connection, your available bandwidth, how your network assigns IP addresses, how many simultaneous calls you need, and which codecs you use. There are three ways to connect: SIP Trunk, SIP Registrar, and IAX. Each one carries its own trade-offs. If you have never done this before, the choice can look intimidating. It does not have to be. This guide walks you through the variables in order, from your internet connection up to your telephony needs, so you can land on a setup that genuinely fits. We will start with the fundamentals, then build toward a clear recommendation. ## What is VoIP? Telecom, and VoIP in particular, is full of acronyms that can put newcomers off. We will keep things plain even if you are not an expert. VoIP is a group of technologies that deliver voice and multimedia communication over the internet. Instead of relying on the Public Switched Telephone Network (PSTN) that carries traditional landline and mobile calls, VoIP uses IP networks, which brings several advantages. It can run over the public internet or inside a private network, such as a company LAN. The voice signal is digitized and split into packets, which makes transmission far more efficient. Because the audio is digital, several calls — what we call "channels" — can share the same line at once. In the legacy phone system, one line essentially meant one call. VoIP needs either dedicated hardware (a VoIP phone) or software, and it is the foundation under many everyday apps for voice and video calling. Since VoIP rides on the internet, the quality and characteristics of your connection are the single biggest factor in call quality. That is where we go next. ## Capacity planning and sizing Bandwidth — the maximum transfer rate of your network — ultimately sets how many channels (simultaneous calls) your setup can handle. But bandwidth is not the whole story. Depending on your configuration, you can compress the signal to reduce the bandwidth each channel needs, which lets you fit more channels into the same connection. To size your installation correctly, you need two numbers: 1. The maximum bandwidth and ping of your internet connection. This part is straightforward. 2. The codec you will use, since it determines how much bandwidth each call consumes. This takes a decision on your part. Together, those two figures tell you how many channels your setup can support. ### Measuring your bandwidth and ping Free online tools can measure the maximum upload and download speed of your connection along with its response time (ping). Any reputable speed-test service will do. Your upload speed is usually the limiting factor, because most consumer connections are weighted toward download. Ping is the time a packet needs for a round trip. On its own, ping is not the main driver of call quality — what matters more is its stability. Ping spikes are what you hear during a conversation. As a rule of thumb, aim for a ping below 40 ms. Above 120 ms you will start to notice the delay, and above 160 ms the line becomes choppy. One caveat: internet service providers often optimize for these tests, so results reflect a best-case maximum rather than the speed you can count on day to day. ### Codecs: what they are and what they do Sending an audio stream — your voice, for instance — over a digital medium means converting an analog signal (sound in the air) into a digital one (your voice encoded as ones and zeros). #### What codecs do A codec handles both the encoding and the decoding of the voice signal. If the caller uses a given codec, the recipient needs the same codec to decode it. Beyond transmission, a codec can also compress the data to shrink its size and lower the bandwidth each call needs — but compression costs quality. There are two broad families. "Lossy" codecs compress aggressively; "lossless" codecs prioritize preserving the original quality. Each codec is optimized for a specific use. Voice calls demand very low latency between encoding at the source and playback at the other end, so telephone codecs are typically lossy: they cut bandwidth and keep latency minimal at the expense of audio fidelity. That is the origin of the familiar "telephone voice." #### The codecs Callr supports Callr relies mainly on two codecs. Both are widely used across the telecom industry, which keeps interconnection smooth. - **G.711 / PCM (lossless):** PCM delivers very high quality, but it is uncompressed and needs a lot of bandwidth. It comes in two slightly different variants — μ-law (PCMU), used in North America, and A-law (PCMA), used elsewhere. - **G.729 (lossy):** G.729 is built to reduce the bandwidth an audio signal needs. It compresses the stream heavily while keeping quality good enough for phone calls. Your bandwidth requirement follows directly from your codec choice. G.711, being lossless, is demanding: a standard ADSL line might support only 10 to 12 channels. Because G.729 compresses the signal, the same line could carry up to roughly 100 channels. | Codec | Type | Quality | Bandwidth per channel | Channels on a standard ADSL line | | --- | --- | --- | --- | --- | | G.711 / PCM | Lossless (uncompressed) | Very high | High | ~10–12 | | G.729 | Lossy (compressed) | Good (phone quality) | Low | ~100 | ## Authentication: dynamic vs. static IP addresses The way your network assigns IP addresses is another deciding factor between SIP Trunk, SIP Registrar, and IAX. It has no bearing on the number of channels you can run, but it is central to authentication. Before we get into the options for each network type, a quick refresher. ### What IP addresses are and why they matter for VoIP Every device on the internet is assigned an IP address, which may or may not be unique to that device. There are two assignment modes: - **Static IP address:** a fixed address tied to a given device. It stays the same even after the router or device reboots. Because it is constant and unique, it can be used to authenticate its owner. - **Dynamic IP address:** the network assigns an address each time the device connects. Because it changes over time, it cannot be relied on for authentication. Other mechanisms can also change the address your traffic appears to come from — Network Address Translation (NAT) being the most common — which affects authentication too. We cover NAT below, but first, why IP matters for SIP Trunk authentication. ### Authentication by IP address Callr SIP Trunk authenticates by IP, so it will not work with a dynamic IP — you need a static address. IAX and SIP Registrar, by contrast, use the Password Authentication Protocol, so they work fine on a dynamic IP. ### Where NAT and VoIP collide NAT hides private IP addresses behind a single public one, letting many devices on a LAN share that one public address. All outgoing traffic passes through a NAT router, which swaps the source IP for its own public address. SIP Trunk uses two separate data streams — one for signaling and one for the audio payload — and the port carrying the audio is chosen at random. So even when the NAT router handles the signaling, it has no way of knowing which audio stream that signaling is paired with, or where to send it. From the user's point of view, the result is one-way audio or no audio at all, despite signaling that looks healthy: the phone rings, the caller hears the ringback, the called party sees the caller ID, the ringing stops on pickup — but there is no voice. Because IAX carries both signaling and audio in a single stream, it sidesteps the NAT problem entirely. ### Reaching Callr's infrastructure You can reach Callr through two entry points. It is good practice to use both in round-robin, splitting your traffic across them to reduce the risk of an outage taking your installation down. #### Firewalls A firewall controls traffic against a set of security rules, usually a whitelist of approved IPs so that authorized applications keep their access. If you restrict inbound or outbound traffic, you will need to allow the right addresses and ports for Callr's SIP service to work. The specific IP ranges and ports to whitelist — including the RTP port range and the SIP signaling port — are documented in the Callr Console and our developer docs; configure your firewall to match. ## The three paths to VoIP With the underlying technology and its challenges in hand, we can compare the three implementations on equal footing. ### The SIP protocol SIP is the industry-standard protocol. A wide range of manufacturers support it, and its request-response structure is easy to work with: a client sends a request, the server replies with a response that always begins with a status code. That model will feel familiar to most developers, because SIP reuses much of the HTTP request/response model, including its status codes. As a result, SIP installations are relatively easy to debug. As noted earlier, voice in VoIP is "packetized" — bundled into packets. A SIP call exchanges two kinds: - **Signaling packets**, which set up the call (for example, negotiating a shared codec) and keep it alive. - **Media packets**, which carry the conversation itself. SIP Trunk gives you full control over your phone system. SIP Registrar is a more accessible on-ramp to SIP: it works with softphones, which makes the initial setup considerably simpler. #### SIP Trunk SIP Trunk is the industry standard and generally delivers the best call quality, with broad gateway compatibility. It requires a static IP, since the IP is used for authentication. That reliance on IP means SIP Trunk can run into trouble behind NAT. #### SIP Registrar SIP Registrar is aimed at the end user and comes with many built-in features — some gateways even require it. It is more constrained than SIP Trunk, though: a few features, such as custom caller line identification (CLI), are not available on Callr SIP Registrar. Like SIP Trunk, it can have issues with NAT. ### IAX IAX (Inter-Asterisk eXchange) is a different approach altogether, with clear advantages on low-bandwidth connections. It uses a single stream for both signaling and media, which makes it far less resource-hungry. It authenticates with the Password Authentication Protocol rather than by IP, so it works on a dynamic IP and handles NAT and firewalls cleanly. Callr's IAX setup also ships with a full set of codecs, which makes international calling easier and saves you the effort of configuring them yourself. The main constraint is that IAX is built on Asterisk — an open-source telephony platform — so you must use an Asterisk gateway to run it. Overall, IAX is a strong alternative to SIP Trunk for installations with complex network setups. ## Finding your VoIP fit Here is the short version to guide your decision: - **Static IP, want the best call quality and full control?** Choose **SIP Trunk**. - **Want a quick, softphone-based setup, or your gateway requires it?** Choose **SIP Registrar** — just note its feature limits, such as no custom CLI. - **Dynamic IP, behind NAT, limited bandwidth, or running Asterisk?** Choose **IAX**. We hope this helps you settle on a VoIP implementation that fits your needs. If any questions remain, our team is happy to help — get in touch and we will walk through it with you. --- # From Numbers to Trunk Management: The Self-Serve VoIP Platform *2025-02-18 · Callr* Set up SIP and IAX trunks, buy numbers in 30+ countries, and track voice usage from one self-serve VoIP platform — built on Callr's owned EU carrier network. VoIP changed telecommunications for good. For decades, businesses in most countries had little choice but to buy telephony from a handful of incumbent providers, accepting whatever packages happened to be on offer. That era is over. With SIP trunking, IAX, and the other protocols that carry voice over IP, any company can now build a setup that matches exactly what it needs. This post introduces the self-serve VoIP platform in the Callr Console: a single place to provision and manage a VoIP installation on your own, buy phone numbers in more than 30 countries, configure your trunks, and review the stats on your inbound and outbound voice traffic. ## Why use VoIP? Compared with a traditional PSTN setup, a VoIP installation has clear advantages. Three stand out: 1. **Faster to deploy and easier to maintain.** All you need is software and an internet connection, which removes most of the friction from the install. Once you are live, scaling up or down costs nothing extra in setup. 2. **Lower cost.** If your business makes a high volume of outbound calls — especially international ones — VoIP is almost always the cheaper option. 3. **More control.** You get a full range of call features at your fingertips: call tracking, call recording, cascading call forwarding, and more. The trade-off worth naming: VoIP quality depends entirely on your internet connection. If your link is slow or unreliable, you won't get the benefits VoIP promises. ## VoIP, entirely self-serve Everything starts from a dashboard in the Callr Console. It surfaces the key metrics for your account alongside the resources you need to get going. Your current balance lives here too, and you can top it up directly from the web with a card or by bank transfer. ### Manage SIP trunks and IAX accounts In the VoIP section, you control your SIP origination and termination trunks as well as your IAX accounts. You can create new trunk groups and IAX accounts yourself, without raising a ticket. For each trunk group you can set the number format and cap the number of channels it is allocated. You can also enable or disable a trunk group — or an individual IP address — directly from the interface. ### Account-level settings You can view and adjust your account limits from the platform, including CPS (calls per second), inbound and outbound channels, and your top-up limits. New accounts start with conservative limits. This is deliberate: it keeps the platform from being misused for fraud or abuse. As soon as you contact support and confirm you are a legitimate business, we raise the call capacity allocated to you. ### Resources to help you get started Need a hand setting up or troubleshooting your installation? A few resources cover the essentials: - The Callr SIP trunking guide, with everything you need to get started and sample configurations for Asterisk and FreeSWITCH. - The SIP and IAX section of the documentation, including a SIP FAQ and a reference list of SIP response codes and their meanings to help you debug. ## Buy phone numbers in 30+ countries You can purchase new numbers (DIDs) straight from the platform. If you are not fluent in telco, here is a quick guide to the parameters you choose when buying a number: - **Country** — self-explanatory. - **Type** — "Geographic" numbers are tied to a location; "Personal" numbers are mobile numbers. - **Class** — "Gold" numbers are easy to remember because the digits are sequential, repetitive, or both; "Classic" numbers are everything else. - **Area code** — for geographic numbers, you can pick the region. People are more likely to answer a call from a local number. - **Quantity** — anywhere from one number to thousands. - **Attribution mode** — when you buy more than one number, this sets the relationship between them. *Random* leaves the allocation to chance. *Sequential* assigns numbers that follow one another — for example, +33 1 99 00 10 20, +33 1 99 00 10 21, and +33 1 99 00 10 22. Buying happens in two steps: 1. **Reserve.** You specify the parameters above, and we return the list of numbers that match your request. 2. **Confirm.** You review the allocated numbers and their cost, then complete the purchase. The reservation step lets you check each number and its price before you commit. Phone numbers are billed monthly, and each month you receive an email recap of your number-related charges. On the numbers tab you can assign numbers to a trunk or IAX account — one at a time or in bulk. The documentation has a full section on number management, including how numbers work at Callr, how to customize the SMS sender ID, and how number portability is handled. ## Analytics and reporting In telephony, analytics matter. The self-serve VoIP platform gives you the metrics you need for a complete picture of your calling activity. Many customers rely on us for high-quality, cost-effective international calls, so the reporting is built for that. You can break your stats down by country in a detailed list, or read them at a glance on a world map. Across Callr products, **campaign reporting is built on top of your contact list**. That helps you qualify your contact data and ensures no prospect is contacted twice within the same campaign — useful enough that some teams use it to clean their databases. ## One platform for voice and SMS **Callr is a full voice and SMS platform — it does much more than SIP.** Alongside your outbound voice campaigns, you can use the REST API to add call tracking to your inbound numbers, send SMS, or route incoming calls in real time. New to APIs? The documentation covers the basics to get you started. ### Call tracking Call tracking captures data on incoming calls. Combine it with a thoughtful number-allocation strategy and you can measure the ROI of your offline marketing precisely — tying a specific number to a specific campaign and seeing exactly what drives calls. ### Build campaigns without code with Callr Actions Callr Actions is the low-code way to combine calls and SMS into a single flow. You build a **scenario** — no engineering required — to handle everything from reminders and notifications to multi-step outbound campaigns. Over the years we have seen teams put these scenarios to remarkably creative use. ## Grow your business, one call at a time With a SIP or IAX installation, you can put phone calls to work at scale. For all the channels that have arrived since — social, messaging, email — a phone call is still one of the most reliable ways to reach a prospect. Those newer channels have their place, but it would be a mistake to write off the phone. Outbound calls still play a significant role in strong acquisition strategies. One reminder: make sure your outbound calling practices are GDPR-compliant — Callr's owned EU carrier infrastructure keeps your voice data resident in the EU by default, which is a solid foundation to build on. --- # Telecom Acronym Reference: A Plain-English Glossary *2025-02-04 · Callr* A clear, practical glossary of the telecom acronyms you actually meet building voice and SMS — from API, CDR and DID to SIP, RTP and VoIP. Telecom is one of those fields where the core ideas are simple but the vocabulary gets in the way. The moment you start building anything with voice or SMS, you run into a wall of acronyms — and most explanations either skip the detail you need or bury you in it. This reference aims for the middle ground. It covers the terms you genuinely encounter when working with phone numbers, calls, messaging and VoIP, with enough depth to be useful and no more. Use it as a glossary you can come back to. ## Common acronyms These are the terms that show up across almost every telecom and messaging project. | Acronym | Stands for | What it means | |---|---|---| | **API** | Application Programming Interface | If user interfaces are how people use computers, APIs are how computers use each other. An API defines a standard way for one program to talk to another without needing to know how it works inside. Callr exposes a REST API and webhooks so you can build voice and SMS interactions programmatically. | | **CDR** | Call Detail Record | The data produced for every call: start time, duration, hangup time and hangup cause, among other attributes. Analyzed in bulk, CDRs reveal usage patterns and are invaluable for diagnosing and debugging your call flows. | | **CLI / CID / CLID / CLIR** | Caller Line Identification / Caller ID | Identifies the number a call originates from. It can be presented or withheld (CLIR is the restriction of that presentation). The SMS equivalent is the Sender ID, which can be alphanumeric or numeric depending on whether replies are needed and on the rules in each country. | | **DID** | Direct Inward Dialing number | Originally a way for a company to assign a range of numbers to individuals without a dedicated PBX line each. Today it simply means a phone number you can buy or port. | | **DLR** | Delivery Receipt / Report | The status a mobile network returns to the sender of an SMS, with its timeline — created, sent, received and updated dates. Webhooks let you react to each DLR the moment it arrives instead of polling for it. | | **DTMF** | Dual-Tone Multi-Frequency | The system behind the tones you hear when pressing keys on a phone. Each key sends a unique combination of a row tone and a column tone. It replaced rotary dialing and is what powers IVR menus, where each key is bound to a different action. | | **E.164** | International numbering plan | The international standard for phone numbers: a `+`, a country code of one to three digits, then up to fifteen digits in total for the subscriber number. | | **IVR / VRU** | Interactive Voice Response / Voice Response Unit | Technology that lets a caller interact with a computer over the phone using key presses (DTMF) and speech. It's used for purchases, lookups, banking, support and call prequalification, on both inbound and outbound calls — though inbound is by far the most common. | | **LVN** | Long Virtual Number | A standard-length number (for example `+44 9865 80044`) used to receive both SMS and calls. Compared with country-specific, sometimes-shared shortcodes, an LVN is available internationally and dedicated to you. | | **MO / MT** | Mobile Originated / Mobile Terminated SMS | MO messages travel from a customer's handset into your system. MT messages travel the other way — from your system out to a customer or prospect's mobile. | | **PSTN** | Public Switched Telephone Network | The combined telephone networks run by local, regional and national operators — the traditional infrastructure that carries calls. Shared standards let these networks interconnect seamlessly across countries. | | **QoS** | Quality of Service | The overall performance of a telephony network as experienced by the people using it. It's judged on response time, signal-to-noise ratio, echo, crosstalk and dropouts, and it matters most for VoIP and SIP. | | **VoIP** | Voice over Internet Protocol | A set of technologies for carrying voice and multimedia over the internet instead of the PSTN. It relies on protocols such as SIP and RTP, and underpins most software calling today. | ## VoIP-specific acronyms Once you go deeper into VoIP, a second layer of vocabulary appears — mostly the protocols and metrics that make internet calling work. | Acronym | Stands for | What it means | |---|---|---| | **ACD** | Average Call Duration | The mean length of calls in a given context — a simple but telling operational metric. | | **ASR** | Answer-Seizure Ratio | The percentage of calls that are answered out of the total attempted. It's a useful indicator of call quality and route health. | | **IAX** | Inter-Asterisk eXchange | A VoIP protocol native to the Asterisk PBX, well suited to setups with limited bandwidth. It carries signaling and media in a single stream, uses Password Authentication, and works well through NAT and firewalls. | | **NAT** | Network Address Translation | A technique that remaps IP addresses by rewriting address information in packet headers — rerouting traffic without changing the addresses of the hosts involved. It eased the shortage of IPv4 addresses and lets many private addresses sit behind a single public one. | | **PBX** | Private Branch Exchange | The system that sits between a company's internal phone network and the public network, connecting internal extensions (short numbers) to each other and to the outside world over the PSTN. | | **RTP / SRTP** | (Secure) Real-time Transport Protocol | The protocol for delivering audio and video over an IP network. It takes over from SIP once a session has been set up, handling the actual media stream; SRTP is its encrypted form. | | **RTCP** | RTP Control Protocol | RTP's companion protocol. It monitors transmission statistics and quality of service, synchronizes multiple streams, and feeds back QoS information at regular intervals. | | **SDP** | Session Description Protocol | A format for describing how a streaming-media session should start. It handles session announcement and invitation, and lets the two parties negotiate parameters such as which codecs to use. | | **SIP** | Session Initiation Protocol | The signaling protocol that sets up communication over IP — voice, video or text. It makes sure each party can locate the other (by IP address) and agree on compatible codecs, then hands the media over to (S)RTP. In practice the term is used more loosely to cover IP voice in general, including SIP trunks and registrars. | ## Where to go next Telecom fundamentals — numbers, delivery receipts, character encoding, codecs — are worth understanding once and reusing forever. For the official, up-to-date detail on how these concepts map to the Callr REST API and webhooks, see the [Callr documentation](https://docs.callr.com). And if you're building voice flows, Callr Actions lets you assemble an IVR or a voice AI agent as a scenario without writing the telephony plumbing yourself. --- # Introducing the Callr Tech Blog: a closer look at our telco infrastructure *2025-01-21 · Callr* We're opening up the engineering behind Callr's telco platform — and open-sourcing tools like our Kamailio exporter for Prometheus. Here's why. Running a telephony network is an unforgiving engineering problem. We've spent years building and operating one, and we've decided it's time to share more of what we've learned. That's why we launched the Callr Tech Blog — a place to go deep on the systems, the trade-offs, and the tools that keep voice and messaging flowing. ## Why open up the engineering side Our main blog has always covered telco topics for a broad audience: how communications power the sharing economy, how AI agents change customer interactions, the occasional hands-on tutorial built around our REST API. We've worked hard to keep that writing accessible to non-technical readers. But telephony is a genuinely hard technical challenge, and we've wanted to dig into the details for a long time. The Tech Blog is where we do that — written by the engineers who build and run the platform, for the engineers who care about the same problems. ## Why latency is the whole game Voice is far less forgiving than the web. A slow web request is annoying; a slow phone call is broken. As our CTO Florent puts it: > "In the telco world, latency is everything. If your web app is overloaded and a request takes five seconds to reply, that's painful — but it still works. On a phone call, latency eventually breaks the line. A 250 ms delay is enough to make audio choppy." That constraint shapes nearly every decision we make about routing, signalling, and infrastructure. It's also why the lessons translate well beyond telephony: anyone wrestling with scalability and latency at scale will recognise the same battles. ## Open-sourcing our tools The Tech Blog isn't just writing — we're releasing some of the tooling we use in production. We're starting with a Kamailio exporter for Prometheus, so other teams running SIP infrastructure can get proper observability into their stack. The telco community has historically kept its solutions to itself. The wider web runs on shared code, shared experience, and shared fixes — and we think operating a telephony platform should be no different. Contributing back is overdue, and this is our first step. ## Dive in The Callr Tech Blog covers our engineering work, the technologies behind the platform, and how we build our products. If you care about voice, SIP, observability, or simply pushing systems to their limits, come take a look. --- # Can SaaS Afford to Leave SMS on the Sidelines? *2017-03-03 · Callr* SMS quietly became the default A2P channel. Here's why SaaS teams use it for onboarding, retention, and customer service — and where it beats email and push. The first SMS was sent in December 1992. In technology terms, that is several lifetimes ago — long enough to have watched pagers, fax machines, and PDAs come and go. So for SaaS companies competing in a crowded market, against a mobile landscape that keeps reshaping itself, a fair question is whether plain text messaging still earns its place. The short answer: yes, and arguably more than ever. Here is why SMS deserves a seat at the table in your SaaS communication stack. ## A quick read on the messaging landscape "Conversational commerce" — brands talking to customers inside messaging apps like Messenger and WhatsApp — moved from buzzword to reality. Messaging platforms now host large numbers of automated assistants, and AI agents have grown steadily more capable at handling real customer conversations. The appeal is easy to understand. Mobile messaging apps reach billions of people, which makes them attractive ground for businesses. But there is a catch: these channels were built for talking to family and friends, so the kind of brand relationship a customer will tolerate there is narrow. For an AI agent to help a brand rather than annoy its customers, it has to stay discreet. The right uses are quick customer-service answers and clearly requested information — not pushing marketing messages into a private chat thread. Dropping a traditional broadcast campaign into someone's Messenger or WhatsApp, however polished the AI agent driving it, reads as intrusive. ## The shift from P2P to A2P As personal messaging apps cautiously opened up to businesses, SMS made the same move. It has been steadily ceding its original role as a person-to-person (P2P) channel and becoming an application-to-person (A2P) one — the messages your software sends to your users automatically. The numbers backed this up early. The A2P share of SMS traffic nearly doubled in the first half of the decade, climbing from roughly 12% to over 22%, and analysts projected A2P volumes in the trillions of messages and a market worth tens of billions of dollars. Retail, finance, transport, healthcare, and logistics led the way, leaning on SMS for order confirmations, transaction verification, delivery tracking, appointment reminders, and results notifications. Critically, consumers welcomed it. Surveys at the time found that a large majority of people were already communicating with businesses by SMS — more than were doing so via chat apps — and a substantial share said they would rather receive product details and updates by text than through other channels. Timely, relevant SMS from a business is not just tolerated; many people prefer it. ## And what about push notifications? Push notifications sit awkwardly in this picture. Industry research flagged a clear case of "push fatigue": more smartphone users were declining notifications, and breaking through the noise had become harder for any app that was not already among the handful of dominant ones. The takeaway was blunt — people were downloading fewer apps, tucking the ones they had into folders, and granting notification permission less often. Push did not die, but it lost much of its reach. If a customer never installs your app, or never enables notifications, push simply cannot deliver the message. ## So what can SMS actually do for SaaS? The way businesses reach customers on mobile has shifted on every front: messaging apps now make room for restrained AI agents, push has lost some of its punch, and SMS has settled into its role as the default A2P channel. At the same time, a tightening SaaS market has pushed many companies toward focused, vertical solutions. SMS — with its renewed A2P purpose — is well placed to help SaaS companies, new and established alike, communicate better with their users. ### SMS for retention and customer service SMS is especially well received for customer engagement and support. Consumer studies have repeatedly found that people see text as a faster, more convenient, and less frustrating way to reach a support team than the alternatives — and that SMS remains, by a wide margin, a preferred way to stay in contact with a brand. A meaningful share of users even say they would rather get loyalty and account messages by text. That maps cleanly onto SaaS, particularly when the goal is reducing churn or delivering timely support. Depending on your trial length, onboarding, and renewal cycle, reducing churn with SMS can take several forms: - Automated reminders so new customers don't miss a kickoff or training session. - Outreach triggered by warning signs — a visit to a downgrade page, or an account that has gone quiet. - A well-timed nudge during a critical renewal window. - A quick, helpful follow-up after someone visits a key FAQ or help page. For moments like these — not worth a phone call, but too time-sensitive for email — SMS is an excellent fit. Text messages carry an open rate around 98%, with most read within minutes of arriving, while emails can sit unopened for days. None of this means email and push have no role; in a multi-channel strategy they clearly do. The point is that SMS provides an immediate, hard-to-miss notification that lands better in certain situations. And because texting is asynchronous, a customer can read, think, and reply on their own schedule — something many people resent being forced to do on a live phone call. As for messaging apps, sending these kinds of operational nudges into someone's Messenger or WhatsApp would, in most cases, feel like an intrusion. ### Offering SMS inside your product Retention is one use; building text messaging directly into your software is another. The same industries already busy with A2P messaging — retail, finance, transport, healthcare, and logistics — are the clearest candidates. Banking, finance, and retail have shown especially strong adoption, with authentication a major driver: confirming a password or transaction by text is now a routine expectation, and these sectors account for a large slice of A2P SMS growth. SaaS providers serving these verticals have a real reason to treat SMS as a capability they offer their own customers, given how readily users in those industries communicate with businesses by message. In a maturing market for vertical solutions, native SMS can also be a genuine differentiator. ## Key takeaways The mobile landscape has made more room for A2P communication over SMS — a shift consumers are both driving and embracing. That opens two distinct opportunities for SaaS companies: using SMS to communicate better with their own customers, and building SMS directly into the product they sell. The verticals with the most to gain are the ones already seeing high A2P activity — retail, finance, transport, healthcare, and logistics. Wherever you sit, SMS is not a relic. It is one of the most reliable ways to reach a person on the device they never put down. Callr makes that practical: a single REST API and webhooks for SMS and voice, running on owned EU carrier infrastructure with EU data residency by default — so you can add messaging to your product without stitching together a stack you don't control.