If you’ve got a phone with a Micro USB power connector (say, for instance, an HTC Android model) and you occasionally find yourself running out of battery power, here’s something that I’ve found to work really well.
A 4xAA to Micro USB battery pack. I’ve stocked mine with Duracell ACCU / Stay charged NiMH batteries so they don’t self-discharge while they’re in waiting.
It’s not a fast charge, but if you can cope with having the phone connected to the charger in your bag / jacket pocket it will get your phone battery back into the green.
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