The problem with using an Intent, is that the result of the Intent Activity is returned via the #onActivityResult method of the originating Activity. Even if we next Activities, the eventual result can still only propagate back to the downstream application thriugh the top level #onActivityResult method. We do not have the ability to directly influence the top level #onActivityResult method, and so cannot retrieve the token result ourselves.

I see two solutions to this problem:

1. Change the oauth2 API to be Intent based. Users' would start our activity to retreive a token, and they would receive their token via their #onActivityResult method. This would mostly involve sticking a facade in front of the current implementation, and would not be too honerous to implement.
2. Consider creating an Android Service to retrieve Oauth2 tokens. We would be able to start Activities and retrieve the result from within the Service. It's a little unclear however as to whether starting intents from a Service is good practice. We would however be able to maintain the same API style that we currently have.