This accessory could almost be proposed by Apple, it is simple, elegant, discreet because perfectly suited to the iPhone 5 / 5s and lightweight efficient. "Almost" because I will issue two reserves: 1- The Juice Pack Air is so adapted to the hull of the iPhone that it is quite difficult to separate faith s installed (okay, it's not every day though .... -> 2!) ; 2- Mophie us "trunk" on features, saying that the JPA enables synchronization with the computer! You have to go in the site FAQ to discover that indeed we can ... via the WiFi connection !!! In my memory, the Juice Pack first generation that I was using my iPhone 4 allowed charge and sync without removing via the micro-USB cable. Well know all computers today use WiFi (if not, you must buy a Mac soon, friends!), This is no big deal in itself, but even so, I note only 4 for the principle ! That aside, this is really great and probably the best external battery for iPhone solution, do not deprive yourself if you want to film long events such as concerts, the best compromise quality / price ratio in my direction 3 models proposed by Mophie ;-)