Fitbit Charge 3 Fitness Tracker
The Charge is Fitbit's best-selling model, and the Charge 3 is the best one yet. Its enhanced heart-rate technology does an even better job of measuring calorie burn and resting heart rate, and an all-new SpO2 sensor tracks changes in blood oxygen levels, letting it sense health indicators like sleep apnea. Its aluminum and Gorilla Glass body is water-resistant down to 50 meters, with an OLED display, expanded smart features, and more than a dozen goal-based exercise modes.