They say they have sleep tracking but if they do I get two and a half hours a night. When in fact I get 8 to 9 hours. I have called many times and they have poorly trained people and what they send in an e mail does not work. They have no user guide so you are on your own. It is great for tracking distance and seeing your heart rate but customer service is non existence. They finally sent me a new HR and it did not work. I just got another replacement and the sleep function still does not work and I have to plug the HR into the computer because it will not sync with bluetooth. I recommend not purchasing a Fitbit!