Just Mobile’s Gum Plus packs an impressive 4,400 mAh of power and 1,000 mA of output. That can charge your iPhone up to four times and is able to juice up your iPhone to 90% in just an hour. With Gum Plus, you can enjoy more music, more video, more talk, more games and more Internet on your iPhone. It also works for your iPod, smartphone and other USB powered devices.