Proper android Oauth2 library / framework [closed]
The most complete library I found is Scribe. I liked it so much that I wrapped it to make it more suitable to asynchronous android interaction. You can check my PostmanLib here. It is supposed to make easier the asynchronous interaction AND the authentication via a webview.
Based on the Oltu (formerly Amber) dev mailing list, it has also been used in Android (at least the client side part).