The WebRTC implementation found at webrtc.org, which is used by Chrome, can also be used by mobile apps, including iOS. It's BSD licensed and used by many mobile apps.
Is there a way to reasonably compile it out as its own so? I looked into it last year and it seemed you could not build Chromium's webrtc independently at all. Mozilla uses it by literally cloning and building Chromium trunk and taking the so out of it.