It’s amazing that in just half a decade, the mobile phone as we once knew has evolved into a powerful mobile PC in your pocket. We’re talking octa-core processors, gigabytes of RAM and storage and even ultra high resolution screens. With all this power though, surfaces a new problem. Battery life. Gone are the days of the hardy Nokias that last weeks on end on a single charge. Sure, mobile makers could always pack in a massive battery, but that has implications in both weight and form factor. Aside from being wall-huggers (which some of us still do), the other real alternative is the external battery pack or popularly known as power bank.