I recommend an app called Bloo. It is free and, in my opinion, better than the official one. It does everything the official facebook app can do (in a slightly different manner, of course) and then some. My favorite thing about this app is its notification system. It notifies you of basically everything. I set my refresh rate to 1 minute, so whenever I see a red notification pop up on my laptop facebook page, i almost autiomatically hear the ring on my phone to notify me. It tells me of wall posts, picture tags, picture comments, etc. Very nice.