Facebook’s latest version of its iOS mobile app is full of new features, the most prominent one being free calls between friends in the U.S. and Canada (everyone else is SOL). Keep in mind the calls are free but if users don’t have unlimited data, they may face penalties from the carrier for going over their limit. While that may be the most exciting feature, the upstate also provides improved social features for liking, sharing, and commenting. [Source: iTunes]