I highly recommend one of these, its 2.1amps per USB port. It can charge two devices at once, comes with a rubberized flat USB cable. Best quality charger I have ever had.

http://www.amazon.com/Ventev-Wallport-universal-charger-separately/dp/B00BEJSRDI/ref=sr_1_1?ie=UTF8&qid=1400085307&sr=8-1&keywords=ventev