I bought one of those battery backup thingies while back just in case. I have yet to use it.
Ha, reading in the shower. I would look silly I think standing there with my glasses on while water rushes down my vision.

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Its like Harry said. It charges really really fast. I can go and wash and some clothes at it would have gained 20% of charging. Just in that short time it takes me to grab the clothes, sort them, put in detergent, set the thing, etc. Or watering my plants outside. That is enough time to fully charge. I read a lot but there is plenty of other things one has to do to live. It tops off so fast. I finally have a phone that tops off fast too.
Still waiting for the self charging kindle with built in solar panels. Somewhere in the body. So it always tops itself off.