What does CelloIP Technologies do?

CelloIP Technologies is a full-service VoIP, WebRTC, AI, and custom software development company based in Ahmedabad, India, serving clients globally since 2016. We build custom Asterisk, FreeSWITCH, OpenSIPS, and Kamailio solutions, mobile SIP dialers for iOS and Android, WebRTC browser-based communication applications, IP PBX systems, call center platforms, and AI-powered communication software. Our team has delivered 500+ communication technology projects for 200+ clients across 30+ countries.

Voice Bot and Voice AI Agent Development

CelloIP is an expert in building AI voice bots and voice AI agents using LiveKit Agents SDK, VAPI, and Retell AI. We build end-to-end STT→LLM→TTS pipelines with Deepgram, GPT-4o, Claude, Whisper ASR, ElevenLabs, and Cartesia. Our voice agents handle inbound and outbound phone calls via SIP trunk integration with Asterisk and FreeSWITCH, deliver sub-500ms response latency, and support multilingual deployments. Use cases include AI customer service bots, appointment scheduling, collections automation, and intelligent IVR replacement.

Custom Software Development Expertise

CelloIP builds full-stack custom software using React.js, Next.js 15 App Router, NestJS, Node.js, Express, Python, and FastAPI backends. Our mobile app team delivers Flutter, React Native, Swift (iOS), and Kotlin (Android) applications — including VoIP dialer apps with CallKit, PJSIP, and ConnectionService integration. We also provide DevOps services including Kubernetes orchestration, CI/CD pipeline engineering, Docker containerisation, Terraform IaC, and multi-cloud deployments on AWS, GCP, and Azure.

Who should hire CelloIP Technologies?

Businesses looking to build or scale VoIP platforms, WebRTC communication tools, AI voice bots, mobile SIP dialers, contact centre software, or custom web and mobile applications should hire CelloIP Technologies. We serve telecom carriers, healthcare companies, fintech firms, SaaS startups, real estate agencies, call centres, and education platforms worldwide. Dedicated developer engagement starts from $25/hr with a 30-day money-back guarantee.

Trusted VoIP & WebRTC Development Partner Since 2016

Build the Future of Communication

Custom VoIP platforms, WebRTC applications, mobile SIP dialers, and AI-powered telecom software — engineered by specialists, not generalists. Asterisk · FreeSWITCH · OpenSIPS · Kamailio.

12+ Years Experience
200+ Global Clients
500+ Projects Delivered
30+ Countries Served

Our Core Technology Stack

AsteriskFreeSWITCHOpenSIPSKamailioWebRTCPJSIPLinphoneFusionPBXSIPFlutterReact NativeNode.jsNext.jsKubernetes
What We Build

End-to-End Communication Technology

From carrier-grade SIP infrastructure to consumer mobile dialers — we cover every layer of modern communication technology.

VoIP Platform Development

Custom SIP servers, softswitches, IP PBX systems, and unified communication platforms built on Asterisk, FreeSWITCH, OpenSIPS, and Kamailio.

AsteriskFreeSWITCHSIPB2BUA
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WebRTC Development

Browser-based voice/video calling, click-to-call widgets, WebRTC gateways, and real-time communication applications without plugins.

WebRTCSIP GatewaySTUN/TURNJanus
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Popular

Mobile SIP Dialer

White-label iOS and Android SIP softphone apps with HD voice, video calling, push notifications, SRTP encryption, and custom branding.

PJSIPLinphoneiOS SwiftAndroid
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Call Center Software

Full-featured ACD, IVR, predictive dialer, supervisor dashboards, and omnichannel contact center platforms with CRM integrations.

ACDIVROmnichannelCRM
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AI-Powered VoIP

LLM-powered conversational IVR, real-time call transcription, sentiment analysis, AI agent assist, and automated CRM note generation.

OpenAIWhisperDeepgramNLP
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OpenSIPS & Kamailio

Enterprise SIP proxies, session border controllers, load balancers, presence servers, and carrier-grade SIP routing infrastructure.

SBCSIP ProxyLoad BalancingPresence
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Custom Software Development

React, Next.js, Node.js, Flutter, and React Native applications designed to work alongside or integrate with your communication stack.

ReactNode.jsFlutterNext.js
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Cloud & DevOps for VoIP

Kubernetes orchestration, CI/CD pipelines, high-availability VoIP deployments on AWS, GCP, or your private infrastructure.

KubernetesAWSCI/CDHA
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Why CelloIP

The Specialist Advantage in VoIP Development

When enterprise communication software fails, business stops. That's why our clients choose specialists over generalists — every time.

Deep VoIP/WebRTC Specialisation

We are not a generalist software shop. Every engineer on our team has been working with SIP, RTP, WebRTC, and telecom protocols for years — not months.

Full-Stack Telecom Ownership

From SIP stack internals to React dashboards to iOS/Android apps — one team owns every layer. No blame-shifting between vendors.

Transparent Partnership Model

Clear contracts, signed NDA on Day 1, full IP ownership transferred to you. We work as your extended engineering team — not a black-box vendor.

Open-Source Foundation

We build on Asterisk, FreeSWITCH, OpenSIPS, and Kamailio — battle-tested, community-supported platforms used by tier-1 carriers globally. No proprietary lock-in.

24x7 Support & SLAs

Production VoIP systems cannot have 9-to-5 support. Our support contracts cover round-the-clock response with defined SLA tiers for critical and non-critical issues.

AI-Native for 2026 & Beyond

We integrate LLM-powered IVRs, real-time transcription, sentiment analysis, and AI call analytics directly into VoIP infrastructure — positioning your product ahead of the competition.

12+
Years in VoIP
Since 2016
200+
Happy Clients
Globally
500+
Projects
Delivered
30+
Countries
Served

CelloIP delivered our multi-tenant IP PBX in 14 weeks — on spec, on time, and with documentation that let our in-house team maintain it confidently. That kind of VoIP depth is genuinely rare.

MR
Mark R.
CTO, US Telecom Operator
Trusted by clients in:USAUKUAECanadaAustraliaGermanySingapore
Technology Stack

Built With the Right Tools

We use battle-tested open-source platforms and modern frameworks — proven at scale by global telecoms, startups, and enterprises.

VoIP Platforms

  • Asteriskv16–21
  • FreeSWITCHv1.10+
  • OpenSIPSv3.x
  • Kamailiov5.x
  • FusionPBXv5+
  • FreePBXv16/17

Mobile & SIP

  • PJSIPv2.x
  • Linphone SDKv5.x
  • Flutterv3
  • React Nativev0.73+
  • Swift (iOS)v5+
  • Kotlin (Android)v1.9+

Web & Backend

  • Next.jsv14/15
  • Reactv18/19
  • Node.jsv20 LTS
  • NestJSv10
  • WebRTCW3C Std
  • WebSocketRFC 6455

AI / Integrations

  • OpenAI APIGPT-4o
  • Deepgram STTv3
  • Whisperv3
  • DialogflowCX
  • SalesforceAPI v58
  • HubSpotv3 API

DevOps & Cloud

  • Kubernetesv1.29+
  • Dockerv25
  • AWSEC2/ECS/EKS
  • GitHub ActionsCI/CD
  • Prometheusv2.x
  • PostgreSQLv16

All platforms and versions kept current — we stay ahead of deprecation cycles and security advisories.

Our Process

How We Deliver Zero-Surprise Projects

A repeatable, transparent process refined across 500+ communication technology projects.

01
01

Discovery & Requirements

We start with a deep-dive technical discovery call to understand your infrastructure, use cases, integration requirements, and growth targets. You leave with a clear scope document.

Scope Document + NDA1–3 days
02
02

Architecture & Design

Our senior architects design the system: SIP topology, codec selection, failover strategy, database schema, API contracts, and UI wireframes. We challenge assumptions early — not mid-build.

Architecture Blueprint3–5 days
03
03

Iterative Development

Development in 2-week sprints with working demos at the end of each sprint. You see real progress — not a 3-month blackout. Feature branches, code reviews, and automated testing at every merge.

Sprint Demos + Code AccessWeeks 2–12+
04
04

QA & Performance Testing

Load testing under realistic concurrent call volumes. SIP conformance testing. Cross-device testing for mobile apps. Security review for SRTP, TLS, and authentication flows.

QA Report + Test Coverage1–2 weeks
05
05

Deployment & Go-Live

Production deployment to your infrastructure or cloud. DNS cutover, monitoring setup (Prometheus, Grafana), health checks, and go-live support with your team present.

Live System + Runbook2–4 days
06
06

Ongoing Support & Growth

Monthly retainer or per-incident support contracts. We proactively monitor your system, apply security patches, and help you scale as call volumes grow.

SLA Contract + 24x7 SupportOngoing

Ready to Build Your Communication Platform?

Talk to a VoIP specialist today. We'll review your requirements, suggest an architecture, and send a no-obligation proposal within 48 hours.

✓ NDA Signed on Day 1✓ Free Technical Consultation✓ Proposal in 48 Hours✓ No Lock-in Contracts

We respond to all enquiries within 4 business hours · Available Mon–Sat, 9am–7pm IST