Use peer-to-peer protocol to broadcast your video over 20+ users.
This module simply initializes socket.io and configures it in a way that single audio/video/screen stream can be shared/relayed over unlimited users without any bandwidth/CPU usage issues. Everything happens peer-to-peer!
This demo has built-in (open-sourced) cordova apps both for iOS and Android.
Google AppStore Link: https://play.google.com/store/apps/details?id=com.webrtc.scalablebroadcast