The earlier Juice Pack was on all the time, for this newer model Mophie also included an on/off switch for the battery; so you are not left wondering if the iPhone is being charged. The four LED charge status lights found on the original Juice Pack are still found on the back of the Mophie Juice Pack Air. Now you can carry an iPhone 3G with three times the battery capacity, all in a protective hard shell case.



Link: TestFreaks