Fitbit, the fitness company behind the Fitbit line of wearable activity tracking devices, today updated its Fitbit iPhone app with a new “MobileTrack” feature, which is designed to offer iPhone 5s users standard Fitbit activity tracking without the need for one of the company’s fitness bands. To track movement and activity, the revamped Fitbit app uses Apple’s “M7” motion coprocessor. First introduced with the iPhone 5s, the M7 chip accompanies Apple’s standard A7 processor and captures motion data from the phone’s co
