Whether you need to top off your device steadily throughout the day or you just like to have an option on standby in the event you need a full charge, a power bank can be a nifty item to have in your back pocket, though not literally of course as they can be a little thick. That being said, they're great for stuffing into a bag or briefcase and toting around for when you need it. Anker makes some of the best power banks around and right now they're PowerCore Speed 10,000 power bank is on sale for just $26.99.
This power bank comes with Quick Charge 3.0 technology support meaning if your device also supports this charging standard it'll be able to charge up rapidly for a full battery in much less time than it would take other power banks without Quick Charge 3.0. For those devices which don't support the standard though, the PowerCore Speed 10,000 also has Anker's PowerIQ technology built in so it can detect how much of a charge your device's battery can take and then deliver the maximum amount of power so it still gets the fastest charge possible. As the name suggests this has 10,000mAh of battery capacity which should be anywhere from 2-4 charges on a device depending on your device battery capacity, and it has a single USB port, as well as a micro USB port for charging the power bank itself when it needs a recharge.