I have three apps on Google Play now (Android Kakuro, Medicine Tracker, and LogicCalc) and had to create help documentation for all of them. I looked long and hard before settling on this mechanism along with jQuery-mobile to provide reasonably good looking documentation.
It took a little playing around to get it all working correctly but is remarkably simple to use overall (and looks pretty good, too). Perhaps an update to this article discussing the use of a library like jQuery mobile would be useful as well.
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