The Sims Facebook app. The Sims have a Facebook app. The Sims version of a Facebook app.
I hate all of those sentences, because none of them look correct. Anyway, so far not bad. It seems to lack annoying friends or spamming Facebook with news feed posts but that might change.
They relaunched this (I guess?) and I am playing it now. Not too U NEED FRIENDZ needy out of the gate, although obviously having a couple playing is better than no one, unless you really love doing their quests (which are pretty ignorable it seems to me). Then you need friends.