No single portable charging device will suit anyone. People who travel light and are looking to add the least amount of weight and bulk to their carry-on bag should consider Mophie's Juice Pack Powerstation Pro. It's small and light, but rugged; it charges quickly over Micro-USB; and it will deliver several additional hours of life to your iPad. If you value power over portability, the HyperJuice Plug 15,600mAh is one of the highest-capacity batteries here. It can handle two iPads at a time, and its convenient built-in plug means that you won't need additional cables or adapters to recharge the battery itself.
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