Heart rate watch features
The heart rate watch measures the heart rate of the human body by sensing the cardiac current of the human body. 

GPS watch function
The GPS watch calculates the distance moved per unit time by receiving the satellite position signal WAYPOINT, and calculates the moving speed. The accuracy of the position signal is determined by the strength of the satellite signal and the sampling rate. For example, the accuracy of the sampling rate of 1 second is obviously higher than that of the sampling rate of 60 seconds. But too high a sampling rate will cause the battery to drain too fast. Its advantage is that it can record the trajectory of the movement and synchronize it to the map.
Pedometer function
The motion sensor of the pedometer watch is a 3D acceleration sensor, which can sense the three-dimensional motion acceleration generated when the human body is moving, such as walking and running, so as to record the number of steps per unit time. Calculate the movement speed and distance of the human body through the input step length, and calculate the calories consumed through the input weight. Its advantage is that it can be used for outdoor and indoor sports, is not affected by the weather and saves power, and can store several days of sports data.