sinch-in-app-callinglisted

# Sinch In-App Calling ## Overview Real-time voice and video SDK for **Android**, **iOS**, and **JavaScript (Web)**. Connects to Sinch's cloud for signaling and routing. ### Supported call types - App-to-App (VoIP/WebRTC between users) - App-to-Phone (call PSTN numbers) - App-to-SIP (connect to PBXs, contact centers) - App-to-Conference (multi-party calls) - Phone-to-App / SIP-to-App (inbound calls) ## Agent Instructions ### Prerequisites The user needs a Sinch account with an application key and secret from the [Sinch Build Dashboard](https://dashboard.sinch.com/voice/apps). See [sinch-authentication](../sinch-authentication/SKILL.md) for credential setup — In-App Calling uses **application-scoped** auth (Application Key + Application Secret). ### Integration workflow 1. **Detect the platform** from the user's project (language, build system, framework): - Android (Kotlin/Java, Gradle) → Read `references/android.md` - iOS (Swift/ObjC, Xcode) → Read `references/ios.md` - JavaScript/Web (npm, browser) → Read `references/js.md` - If unclear, **ask the user**. 2. **Walk through the integration steps** in the platform reference. Go step by step — confirm each step is in place before moving to the next. 3. **Ask about auth approach**: Can the Application Secret be embedded (prototyping only) or must JWTs come from a backend (production)? 4. **Ask about call types**: Which types does the user need? This determines which sections to cover. 5. **For Phone-to-App