Most small electronic items feature USB chargers today. This means they might have to get charged away from another device, just like a laptop or computer, that has a USB port. Despite the fact that USB charging has become pretty pervasive, it may also be inconvenient. However, power bank chargers give a fast, far more convenient, and in many cases safer solution.
http://www.youtube.com/watch?v=eBlTKreXpMk
http://vid.me/s6QB