The purpose of using a fitness tracker is to monitor physical activity, track progress, and promote accountability. These devices typically record metrics such as steps taken, heart rate, and calories burned, providing users with insights into their fitness levels. By setting goals and receiving real-time data, users are more likely to stay motivated and adhere to their exercise routines. Furthermore, fitness trackers can help identify trends, allowing for adjustments in workouts and fostering a deeper understanding of personal fitness journeys.