Facebook and iOS

Is there an open source API that allow me to post on 开发者_StackOverflow社区groups of Facebook? Secondly, do I need to create an application for that or no need? I'd like to do that through iOS.

You should be able to use the Facebook Graph API and simple HTTP requests (using the iOS SDK) to do this. There's also an actively developed open source Facebook iOS SDK that should make this process even easier.

FaceBook has an API - have you checked to see if what you want to do is supported?

As far as their being a need - FaceBook has their own iOS app. Do you want to do something that it can't already do?