On the look out for the best solar phone charger? We know 'Low Battery Anxiety' is a thing. Ok, perhaps not a real illness or disorder, but research shows that nine out of ten people panic in some form or another when the dreaded warning appears on their cell. Sure, you can always stash a few charging cables in your bag, but if you're off the grid, or mindful of your carbon footprint (as we all should be), a portable solar charger is the way to go. These seven picks are water proof, lightweight, and rev up your device in decent time.