We just talked to Nike last week about its Nike+ GPS app for the iPhone, and there's another update to the already full-featured app. A new feature called Tag brings competition into Nike+ GPS. After you finish a run in the app, you can press the Tag button to invite as many of your friends or contacts to the game as you want; each user invited has to complete a certain goal within three days. The goal can be set for distance, time, or the last person to actually go running. At the end of the game, everyone gets to know who was "IT" -- whoever went the shortest or whoever ran last.
It's all meant in fun, but it seems like a cool, social way to keep
