Fitbit updated its iPhone app on Monday to take advantage of the iPhone 5S M7 motion processor, much like the Nike+ Move app released earlier this year.

The Fitbit update allows users to track their activity without Fitbit hardware, which costs about $100 from most retail outlets. The MobileTracker feature within the app doesn't open up every single Fitbit tool, but offers basic functionality like steps, miles and calories burned in a day.

Like the Nike+ Move app, it appears Fitbit's ultimate goal is to get you to buy its hardware. The app is a way to suck users into the ecosystem and make them eventually upgrade to a better tracking experience.

The M7 processor introduced in September inside the iPhone 5S measures user motion data, even while the device is asleep, and saves battery life for a pedometer or other fitness apps that use the accelerometer throughout the day. Apple says it leads to "better fitness and activity apps that go well beyond what other mobile devices offer".

Fitbit also added a slew of other features in the 2.1 update: Silent Alarms settings, ability to set your own custom water goal, a redesigned profile editor, redesigned tracker settings, redesigned sign-up and sign-in, ability to tap on people in Friend Finder to see their profile, swipe on friends on your leaderboard to Cheer, Taunt or Message, and tap on tabs to auto-scroll to the top.

The update is available from the iTunes App Store.