iphone 5

This year Apple has added the new M7 motion coprocessor.

This low-power part's job is to collect data from the integrated sen- sors, including accelerometers, gyroscopes and compasses. It can even do this while the phone is sleeping, making the data it col- lected available to the CPU when it wakes up. Having this means that the phone can use its sensors more without affecting battery life. For example, if you put your phone where it has no signal, say in a locker at the gym, the M7 can use the sensors and work out that the phone's not moving. As it's not moving, it knows it's not worth hunting for a signal, so it can save on battery power.