i can set the back-facing camera in javascript. it is as i told you. flipping back and forth requires other steps which you will have to learn. (i only have a vague understanding of the protocol). assuming you simply want to find some already created webrtc demo, you will need to find one that exposes these necessary steps. injecting the javascript to use front-facing or back-facing camera is trivial once you learn what you need to learn about webrtc.