The pure java script/typescript API and Unity WebGL plugin is now open source and freely available on github: https://github.com/because-why-not/awrtc_browser. It also contains a browser version of the CallApp which can connect to the Unity version out of the box. You can give it a try here.
The first test builds for the unity version of WebRTC Video Chat V0.984 are now available in the download area. The current version is not yet stable but will be updated on a weekly basis until it is ready for release. Please report any errors you find via e-mail or use the github issue tracker. See changelog to learn more about the next update.