Your GPS location (if you have it turned on), your SMS messages, your call logs, your phone's storage, your camera, your mic... Just read the permissions: https://play.google.com/store/apps/details?id=com.facebook.o...

I've never had a Facebook app on any of my phones and I will never install one.

Worth pointing out: Luckily, my phone came without Facebook apps preinstalled, so I had the choice of seeing what Facebook wants to access. Other people don't even have that chance since it comes preinstalled in most of the cases.