As I use my mobile devices more and more, it seems like my batteries last less and less. That’s why I’m keen on having a backup battery handy at all times whether I’m just in the office or on a trip. I’ve used a few different battery cases for my iPhone, but I’ve yet to meet one I actually liked (needless to say, they don’t stay in use for long). Enter MyCharge. This company makes a range of useful portable batteries that can save you when the power on your device is dwindling. I tested out the Peak ($99 at Best Buy), Sojourn ($39.99) Voyage ($39.99 at Best Buy) models. Peak offers the most power at 6000 mAh which translates into 27 hours of talk time on your phone. Peak also lets you charge up to 3 devices at once and works with iPhone/iPad, Android and BlackBerry devices right out of the box. Sojourn and Voyage are very similar but one is for iOS devices (Sojourn) and one is for Android devices. These two devices are much smaller and more lightweight and offer up 4 additional hours of talk time.