I assume he's talking about a "remote" app for Android. There are a dozen for iOS at least. They all work via the HTTP interface that xbmc exposes, I believe.

The android xbmc app is special because it is development by the xbmc team.

xbmc has a few remote apis. The nicest is the JSON one, it's so easy to work with I wrote a simple remote for my n900.

Yes you can control XBMC over JSON-RPC there are many remotes for Android / IOS. I personally use my IPad as remote.