Fitbit Alta fitness tracker has an auto sleep tracking mode. This Fitbit Alta tracker lets you analyze your sleep patterns for better sleeping habits.Track your way to a better night’s sleep with the Fitbit Alta Fitness Tracker. It intelligently tracks how long and how well you sleep. See your sleep trends and get into a better routine. The tracker also lets you set a silent alarm with the help of the Fitbit app so that you wake up peacefully and get ready to face the day without the noise of an alarm still going off in your head. This Fitbit wearable syncs wirelessly to computers and more than 200 devices and lets you log your food intake, record workouts, explore your trends, and connect with friends, all under one roof. Available in a combination of silver and plum, the Fitbit Alta fitness tracker helps you reach your fitness goals.