Many fitness trackers in the past have been shown to be woefully inaccurate despite the entities selling them insisting that they can save your life as though the little computer things are actually magical devices.
http://qz.com/509009/an-apple-watch-saved-a-teens-life-and-t…
Now according to a new study they also appear to fail at making you lose weight. And I don't mean nothing at all happened because in fact the users of fitness trackers gained weight over a 2 year period.
Fitness trackers are so useless