Fitbit Flex Wireless Activity and Sleep Wristband Activity tracking: Track steps taken, distance traveled, calories burned and active minutes. Sleep monitor + silent alarm: Monitor how long and how well you sleep and wake with a silent alarm. Progress display: See LEDs light up as you progress toward your daily goal. Style + accessories: Style the slim, removable tracker your way with colorful accessory bands. Personal dashboard: The Fitbit app is full of graphs, charts, and tools designed to help you track your progress and better understand your health and fitness.