Keeping your small devices powered while far from the electrical grid requires extra equipment. Still, a battery pack can only last so long before it too is depleted.  An answer to that problem might very well be the Goal Zero Venture 30 Solar Recharging Kit ($170).
Coming from the specialists in outdoor-adapted, portable energy at Goal Zero, the kit measures 11″ x 13″ x 3″ and weighs a mere 3.3 pounds, so it can go straight from the airport into the wilderness.  It can be charged (via the built-in Micro USB port) in four hours or through full sunlight on its solar panels in just nine hours. The whole kit is waterproof with an IPX6 weather rating so you don’t have to baby it outdoors.  The 30 Wh, 7,800 mAh battery is said to provide 3-5 phone charges, 5 Go-Pro charges, 3 digital camera charges, or 1 tablet charge for each full charge of its own.  It also has a High-speed USB 4.8A across dual ports for juicing-up multiple devices simultaneously.

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