End-to-end encrypted calls between two contacts over WebRTC. Call
signalling (offer, answer, hang-up) travels as ordinary Signal-encrypted
messages through the relay; media is DTLS-SRTP, peer to peer when
possible and through the operator's TURN server otherwise.
- Non-trickle ICE (candidates gathered for up to 3 s), 45 s ring
timeout, busy handling, and a call log entry in the conversation.
- The system call UI rings even when the app is closed: CallKit from a
PushKit VoIP push on iOS, a full-screen incoming call from an FCM
wake-up on Android. The wake-up carries no caller; the app learns who
is calling from the queued offer once it is unlocked.
- New permissions: camera for video, audio routing and Bluetooth
headsets, network state; iOS background modes audio and voip.
Push on Android: a fresh install now picks UnifiedPush when a
distributor is installed and FCM otherwise, instead of leaving wake-ups
off. Without a wake-up Android puts the app to sleep and messages wait
until it is opened. Users can switch at any time in Settings.
Julius Joska