Works for Nexus 4 and 7 Super / has lots of accessories
EasyAcc® 8400mAh External Battery Pack with LED Flashlight Portable 2 USB Charger Power Bank for iPhone mobile phone Samsung Smartphone Tablet PC GPS - Black (Accessories) 5
EasyAcc® 8400mAh External Battery Pack with LED Flashlight Portable 2 USB Charger Power Bank for iPhone mobile phone Samsung Smartphone Tablet PC GPS - Black (Accessories)
I invite to the battery pack my Nexus 4 and my Nexus 7, it works great. Due to 2A output loading is also quite fast. There are also a large number of adapters, you can upload virtually any device with it.