Fitbit Alta HR

All day activity tracking with continuous heart rate Track calorie burn, heart rate, & gauge workout intensity, Sleep tracking with sleep stages Auto exercise recognition SmartTrack technology automatically detects and logs workouts Smartphone notifications Keeps you connected with call, text and calendar notifications on display Adjustable strap Fits comfortably on most wrists from 6.7" to 8.1" in circumference. Syncs to Apple, Android and Windows devices