Jag tror att det drar minimalt med ström. Den heter motion calibration på engelska och rör M8 processorn (stegräknare m.m).
Motion calibration via the m8 motion coprocessor allows for more accurate and energy efficient motion tracking with additions like a barometer, gyroscope, and accelerometer. These are great for fitness or sports buffs, and especially outdoor enthusiasts like hikers, mountain bikers, or rock climbers.
Improvements made on the M8 motion coprocessor means it has its own dedicated CPU (central processing unit) which actually uses LESS battery power.