What URL does Facebook app use for data? I want to block the Facebook app on my iPhone. I've blocked facebook.com in restrictions and every single Facebook URL for servers I can find - this works great in safari, but open the Facebook app and nothing is blocked. What URL do I need to block to fix this?

EDIT: I know school filters somehow are able to do this so there has to be a URL..
When you are blocking URL in iOS you only block them for Safari and applications using an in-app browser. 

So you won't be able to block Facebook that way.