Jawbone JBR03-MD Up Bluetooth Headset, Medium - Retail Packaging - Black Pairs With Iphone(R) App To Track Steps, Distance, Calories Burned, Pace, Intensity Level, Active Vs Inactive Time, Gps Routes & More Vibrates On User'S Wrist When User Is Inactive For Too Long Automatically Tracks Hours Slept, Deep Vs. Light Sleep, Awake Time And Overall Sleep Quality Replaces Alarm Clock By Vibrating On Wrist To Intelligently Wake The User At The Ideal Moment In Natural Sleep Cycle Tracks Meals And Prompts Users To Respond To Questions To Help Discover Which Foods Make Them Feel The Best