The 2.4A output will charge smart devices quickly. This energy efficient unit has a charging indicator light to indicate remaining power levels. An intelligent power control chip prevents over-charging. A Micro USB to USB cable is included. It will also charge Apple devices, but only when used with your existing Apple charging cable (not provided). Rounded and tactile design with a Lithium-ion battery. With a battery capacity of 3,350mAh, the Juice Pebble won’t let run out of charge!