forum software with a simple RESTful API support

Question

I'm searching for a forum software which offers REST like API. It should be able to respond to simple calls like retrieve-post, add-new-post etc. and return the result set in JSON or XML format.

Those that immediately come to mind are phpBB, Vanilla, and/or vBulletin. But I don't know if they have REST API. Also I don't intend to deploy the forum for a website. I intend to integrate a forum like feature inside the Android and iPhone apps.

Edit: I don't intend to host the server on mobile. Just access it from the mobile app.

thanks