Nike's new Nike+ Move app, first shown off during the iPhone 5 introduction in September, hit the App Store late on Monday. The app takes advantage of the iPhone's M7 motion coprocessor to turn your smartphone into a complete fitness tracking system. It monitors how active you are, much like the Nike Fuelband or Fitbit Flex, compares activity between days, and shows how you stack up against your friends in Game Center. You'll need an iPhone 5s because the app requires the M7 coprocessor to do its thing. The Nike+ Move app is free and is available at Apple's iTunes-based App Store.