Make health a habit. Advanced tracker for activity and sleep. If you want to turn fitness into a lifestyle, the One™ is for you. For starters, it never rests. During the day, it tracks your steps, distance, calories burned, and stairs climbed. Come nightfall, it measures your sleep quality, helps you learn how to sleep better, and wakes you up in the morning. The One™ motivates you to reach your goals by bringing greater fitness into your life - seamlessly, socially, 24 hours a day. Features: • Tracks steps, distance, calories burned, stairs climbed • Measure your sleep cycle • Silent wake alarm • Challenge and compete with friends on Fitbit.com Compatible with: PCs, Macs, iPhone 4S & 5, iPad 3, Retina & Mini, iPod Touch, and select Android devices. See https://www.fitbit.com/devices for a full list of compatible devices.