The $10 Solar Powered Wikipedia Phone eReader MP3 player GPS Unit
How useful is an old cellphone? How about one which is solar powered? The reality is that solar powered cellphones are pretty darn useless. I have a bunch of different types of solar panels, and the best of the portable ones would still need your phone plugged in for hours a day, in direct sunlight, outside (no UV proof glass in the way) in order to get a full charge. A solar panel on the back of your cellphone? Well, how much time does your cellphone spend outside, on it's face, on sunny days? My guess would be none, until it drops out your pocket on the way to the beach (quick tip - get rid of those hipster short shorts). That is unless it's not your cellphone. Just "a" cell phone. Specifically the Samsung Replenish - the only cellphone which comes with an optional solar-charger back. Namely one I bought for $4.55 (including shipping!) on eBay and then added a new in box Samsung battery cover. And an old used 8gb microSD card I had lying around. ...