If you ignore the horribly bad acting in the video below, you’ll soon realise what an awesome product this thing actually is. When people ask how much power you get out of an external portable battery it is always difficult because it depends on what kind of battery you are charging and what you’re using it for. But the Mophie Juice Pack Powerstation PRO packs a punch with 6000 mAh, and will work with most USB devices to keep you going for days. $99.95