Mophie Juice Pack Helium is a battery sleeve that you clip on to your iPhone. The problem with the iPhone is that it’s such a fetching device that you feel like you should be using it all the time, which only makes it run out of juice all that much faster. The Mophie Juice Pack Helium adds another 80 percent of charge, and therefore almost doubles your talk and usage time. You could be tweeting all night without a break, considering that the juice pack gives you another five hours. Physically speaking, it adds just a slim and virtually unnoticeable layer to the iPhone, which also protects the phone from damage when you accidentally drop it or bump into something hard.