ANDROID • FLUTTER • REACT NATIVE
Voice call SDK for mobile apps
Add 1:1 and group voice calls to your Android, Flutter or React Native app with RTCExpress. The SDK handles signaling, WebRTC media, reconnects and TURN relays, so you don't run any servers yourself. Start free with 2,000 voice minutes a month for 1:1 calls.
Pick your SDK
| Platform | Install | Guide |
|---|---|---|
| Android (Kotlin) | implementation("com.devsquarelabs:rtcexpress-android:0.1.0")from Maven Central | Android (Kotlin) guide |
| Flutter | flutter pub add rtcexpressfrom pub.dev | Flutter guide |
| React Native | npm install rtcexpress-react-nativefrom npm | React Native guide |
Building for the browser too? The same calls work in web apps with npm install rtcexpress (Web SDK guide). The iOS side of the Flutter and React Native SDKs is experimental and not yet verified on devices.
What you get
- 1:1 calls: ring a user, accept or reject, mute and hang up, with call states (ringing, connecting, connected, ended) as events.
- Group voice rooms: many people in one call through our media servers, from the Starter plan.
- In-app chat in the same SDK: rooms, message history and presence, so text and calls share one login.
- Secure by default: your backend issues short-lived user tokens; the App Secret never ships in your app.
- Your own UI: the SDK gives you events and methods, and your app keeps its own design.
Build a working call in about 10 minutes
Each tutorial builds a complete app where two Android phones call each other, with accept, mute and hang up:
- How to add voice calling to a Flutter app
- How to add voice calling to a React Native app
- How to add voice calling with a JavaScript SDK (web)
Want to hear the call quality first? Open the live demo on two devices.
Pricing
One flat price per project, with no per-minute billing:
- Free, $0: 1:1 voice calls, 2,000 voice minutes a month, chat for 100 users.
- Starter, $9/month: 30,000 voice minutes and group voice calls.
- Pro, $29/month: 50,000 voice and 10,000 video minutes, plus screen sharing.
Minutes are participant minutes: two people on a 10-minute call use 20. See the pricing page for details, or read what the free plan includes.
Start free
Create a free account, copy your App ID from the console and follow a tutorial above. Questions? Email us and the engineer who runs the platform will reply.