Created on April 20, 2026, 12:33 p.m. - by Primocys, IT Company
When you start building a mobile app or web platform that needs real-time video calling — whether through a peerjs video call setup or a fully managed API — you face an immediate choice: pay for a managed API like Agora, Twilio, or Zegocloud — or build your own real-time communication layer using WebRTC. At Primocys, we deliver self-hosted WebRTC for both mobile apps (Flutter & React Native on iOS and Android) and web applications (React, Next.js, Vue) — same open standard, same cost advantage, same data ownership. This guide gives you the honest numbers, the architecture differences, and the decision framework we use when we build video calling into apps like Corex Messenger and Vemenne.
WebRTC (Web Real-Time Communication) is an open-source standard — built into every major browser and available natively on Android and iOS — that enables peer-to-peer audio, video, and data transmission directly between devices. It is the same technology underlying Google Meet, Facebook Messenger’s video calls, and Discord.
The challenge with raw WebRTC is complexity. You need to manage ICE (Interactive Connectivity Establishment) candidates, SDP (Session Description Protocol) negotiation, STUN servers (for NAT discovery), TURN servers (for relay when direct P2P fails), and your own signalling layer. It is powerful but verbose.
PeerJS is an open-source JavaScript library that wraps WebRTC’s complexity behind a clean API. Instead of managing ICE candidates and SDP offers yourself, PeerJS handles the handshake, NAT traversal, and connection setup — letting you focus on your application logic.
⚡ The key insight: Agora, Twilio, and Zegocloud are essentially “WebRTC-as-a-service” — they host the signalling servers, STUN/TURN infrastructure, and media relay on your behalf and charge per minute for the privilege. PeerJS gives you the same WebRTC standard, but you host the infrastructure yourself, paying only for server costs instead of per-minute usage fees.
One of the most common misconceptions we hear: “WebRTC is for browsers only.” That hasn’t been true for years. At Primocys, we implement self-hosted WebRTC across every platform — and the same infrastructure (your TURN server + signalling server) powers all of them simultaneously.
WebRTC runs natively on both Android and iOS via official platform APIs. For Flutter projects (our primary mobile stack), we use the flutter_webrtc package — a mature, production-tested binding to the native WebRTC engine on both platforms. For React Native, the equivalent is react-native-webrtc. Both connect to the same PeerJS signalling server your web users use — one backend, all platforms.
In web browsers, WebRTC is a first-class native API — available in Chrome, Firefox, Safari, and Edge without any plugin. PeerJS wraps the browser’s RTCPeerConnection API, meaning the exact same JavaScript calling code works across all major browsers. For React / Next.js projects, we integrate PeerJS into a custom hook or context so call state is managed cleanly alongside your application state.
✅ The architecture advantage: Because WebRTC is an open standard implemented at the OS and browser level, a single backend deployment — one Node.js PeerJS signalling server + one Coturn TURN server — serves your Flutter mobile app, your iOS app, your Android app, and your web application simultaneously. You are not paying Agora per-minute for each platform

The architecture difference is fundamental. With third-party APIs, all your call data flows through their infrastructure — every packet, every audio frame, every video frame. With self-hosted WebRTC, direct peer-to-peer connections handle approximately 80–85% of calls, and your own TURN server handles the remaining 15–20% where direct connection is blocked by NAT or firewalls. Your data never leaves your infrastructure.
Let’s use a consistent scenario for fair comparison: 100 daily active users, each making an average of 60 minutes of HD video calls per day, 30 days per month. That’s 180,000 call-minutes per month.

⚠️ Important note on Zegocloud: Zegocloud appears significantly cheaper than Agora and Twilio — and for small-scale apps with 10–50 users, it can be cheaper than self-hosted WebRTC (which has a fixed baseline cost). However, at 1,000+ users, the per-minute model still results in $1,080/month vs $80–$150/month for self-hosted. Additionally, your data still routes through their servers — an issue for enterprise, healthcare, or compliance-sensitive applications.

Here is the minimum viable implementation of a 1:1 video call using PeerJS — the same foundation we use in production chat applications like Corex Messenger and Vemenne, built with our Node.js backend.



✅ That is genuinely the core of a 1:1 video call. Three files, ~60 lines of code. The rest of your implementation effort goes into UI design, call state management (ringing, connected, ended), and TURN server configuration for production reliability — not the call technology itself.
Standard PeerJS uses a mesh network architecture where each participant connects directly to every other participant. This works well for 2–4 users in a call, but becomes bandwidth-intensive beyond that. For a call with 6 participants in a mesh, each person is sending 5 streams simultaneously — which can overwhelm mobile connections.
For group calls with 5+ participants, Primocys implements a Selective Forwarding Unit (SFU) — a WebRTC media server where each participant sends one stream to the SFU, and the SFU forwards the appropriate streams to each participant. This dramatically reduces per-user bandwidth requirements.

The open-source SFU options Primocys uses — MediaSoup and Janus — are the same category of technology Agora uses internally. The difference: Agora hosts it and charges per-minute; you host it on your own server and pay only for compute.
This is not a theoretical comparison. Here is exactly what we implemented in two live applications:
Built for Orbis Elite, Inc
Student & University Messenger
✅ Our standard architecture for all Primocys video calling projects: PeerJS + Coturn TURN server (for 1:1 and small groups) + MediaSoup SFU (for groups of 5+). This stack scales from 10 users to 100,000+ users with only infrastructure scaling — no change to the calling architecture, no change to per-minute pricing, and no change to data ownership.
We don’t just write about building chat apps — we’ve shipped them. Here are two live messaging platforms built and delivered by the Primocys team:

Click Here: Book Mobile App Demo →
Click Here: View Live Web Demo →
Choosing the right real-time video platform in 2026 comes down to one question: do you want convenience or control? Agora, Twilio, and Zegocloud deliver fast setup and managed infrastructure — but you pay per minute, per user, forever. Costs scale brutally as your app grows. A peerjs video call implementation or a fully self-hosted WebRTC solution gives you complete data ownership, zero per-minute fees, and full architectural control — exactly what we build at Primocys for production apps like Corex Messenger and Vemenne.
If you are building a Flutter, React Native, React, or Next.js app and want real-time video without the recurring API bill — Primocys can build it for you.