Works for ePub. Me and the developer created this
Works for Mobi (Same as 4665 posted but this is the current link)
I am trying to work with DK101 to have DarkThumbs support Mobi and Azw, but coding costs money and takes time so I am ...
I have this issue as well
Fix that works for me:
I read somewhere that it could be an issue relating to low battery, but this morning it happened with 54% power.