How to choose input video device for webrtc?

Question

I am studying webRTC application.

My reference is this software

apprtc https://code.google.com/p/webrtc/source/browse/trunk/samples/js/apprtc/

demo

Answer 1

On Chrome:

chrome://settings/content/camera
chrome://settings/content/microphone

On Firefox: media.navigator.permission.disabled=false