About this item

• BATTERY LIFE: Up to 7 days
• COMPATABILITY: Works with iOS & Android
• BUILT-IN GPS: With built-in GPS, leave your phone behind and explore the outdoors with pace and distance on your tracker
• ACTIVE ZONE MINUTES: This feature alerts you to which heart rate zone you’re in so you can see if you’re working hard enough to reach your goals.
• SLEEP STAGES & SCORE: Charge 4 tracks your time in light, deep and REM sleep stages and gives you a nightly Sleep Score in the Fitbit app