The Juice Pack Air from Mophie is a battery case for your iPhone. It protects the iPhone from daily wear and tear while doubling the available power and usage time.
Unlike other cases that try to outdo Apple and end up hiding the beautiful form and shape of the iPhone, this one merely goes with the flow.
The pass-through buttons meld the case and the iPhone into a seamless unit that looks good while providing enhanced protection and functionality.
When your iPhone starts running out of juice, switch on the Mophie Juice Pack and the stored battery power flows into the iPhone.
When both run out of juice, you can charge them simultaneously. You get double the charge in the same charging time