Running out of battery life for your phone when you're just about to meet up with friends is an inconvenience at best, a disaster at the worst. With most devices using the universal standard known as USB for charging, it makes sense to keep a mini-USB charger or two in your home and office. Don't mistake mini-USB for micro-USB, though. Micro-USB plugs are the ones used in many Android smartphones. Mini-USB is a larger standard; it is used DualShock 3 controllers and in some older tablets as well as some phones. Browse through eBay's reliable sellers to find the right charger for you. When purchasing a mini-USB charger, you have several options. Some mini-USB wall chargers are just one cable. Wall outlet adapters, however, allow you to connect your existing USB cable for any device and use it to charge. The latter has the advantage of being compatible with a wide variety of devices, not just mini-USB ones. You can also purchase a mini-USB car charger or adapter so even if you do run low on battery, you can recharge on the go.