I am currently integrating SoundCloud's Java API wrapper into my application. For the purposes of this project, I am required to authenticate with OAuth2 using SoundCloud, Facebook, or Google+. SoundCloud supports this and they have a mobile optimized web URL http://developers.soundcloud.com/docs#mobile. I have a working implementation.
I am working on an Android application that uses the mobile SoundCloud web auth page to log in to SoundCloud. The SoundCloud mobile web auth page provides you with three options for logging in, using SoundCloud, Facebook, or Google+. The interface looks like so:
So far I can log in using my SoundCloud and my Facebook credentials but I fail when using Google+.