Updated Fitbit app uses iPhone 5s M7 chip data

In the newest version of it's iPhone App (version 2.1) FitBit can read the motion tracking data in the M7 coprocessor of the iPhone 5s which continuously collects motion data in the background.

You need to register a free account with FitBit through the app so that it can track the steps you've made, the distance you've gone and the calories you've burned and sync the data with "MobileTrack" to your FitBit accound. First time usera will be asked to answer several questions first such as age, height and weight.