Dixi (2014)

Shari and her friends all subscribe to 'Dixi,' a Facebook-like social network for tweens, where they post updates on what they're doing, share their thoughts, play games, take part in online polls, upload photos and videos, etc. Shari learns that her profile has been hacked--photos defaced and embarrassing, crude, insulting updates added. Not only that, but Shari has also been locked out of her own account. But she won't give up and simply start a new profile; she determines to get her page back AND find whoever did this. But when her friends' pages start getting hacked, they realize that a cyber "serial killer" is on the loose.