Run and recharge your personal battery as well as your mobile phone battery!

In the future, running out of battery on your smartphone might be solved by simply going for a run — thanks to a new pocket-sized gadget that converts physical movement into electricity.

The creators of Ampy say that their ‘wearable battery’ can generate enough electricity from a day’s worth of walking (that’s about 10,000 steps) to charge a smartphone for three hours. And if users need to use their drained mobile in a hurry then they can try more intensive forms of exercise, with an hour of cycling or thirty min utes of running producing the same amount of charge.

The device works by using tried and tested kinetic charging technology, which uses the wearer’s movement to slide magnets back and forth through coils of wire to create electricity. Ampy’s creators say that the device will also store power for up to a week — meaning that users can charge it when convenient and then keep it in their bag to be used later on.