For what its worth, the biggest problem with an iPad (and likely other tablets as well, but that's the one i have experience with) isn't even so much the reading in sunlight, its the HEAT. They overheat rather quickly in direct sunlight, or even in the shade if you live in a warm, southern location, and shut themselves off. Then you have to get it into a cool, AC environment and let it sit for a while before the thing will turn back on. As an outdoor device of any kind its somewhat lacking. Again, though, that may not be much of an issue where you live.
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