Can police track peoples Ip on Ask.fm?

I was wondering if the police can track down peoples ip on ask.fm if they do not have an account or are anonymous. Also, could you still be to blame if you were getting mean things said but you still have your ask.fm page open and sharing it onto facebook? lastly if the person has done it by phone can they still be traced? even if they're phone is completely off i.e battery taken out