With Fitbit Charge 4, theres no limit to how far you can go. This sleek, water-resistant tracker is packed with features that help you know your workouts and your body better, like built-in Gps, Active Zone Minutes, new exercise modes and sleep tracking. Use built-in GPS to see your pace and distance on screen during outdoor runs, rides, hikes and more and see a workout intensity map in the app that shows your heart rate changes along your route. With active zone minutes, feel a buzz when you reach your target heart rate zones during exercise, and celebrate when you earn extra minutes outside of exercise. Use 24/7 heart rate to track resting heart rate & better measure calorie burn. Track workouts in real-time with 20+ goal-based exercise modes. It's also swimproof and water resistant so you can track swims, wear in the shower and more. Track sleep stages & review your in-app sleep score for an easy way to see how well you slept. Get call, text and smartphone app notifications on your wrist. Plus, send quick replies to texts.