Does omniauth act as provider

Hi There,

I got this Problem:

OAuthProvider <-> Rails WebApp <-> iOS App

With omniauth the part between "OAuthProvider" and "Rails WebApp"
seems to be really easy.

But how about authentication for the iOS App. Is there a way to "pass
through" authentication so that I could authenticate the iOS App via
Facebook for my webapp?

Otherwise I need to implement an own OAuthProvider - which makes the
stuff really complicated.

Thanks for your help
PascalTurbo