Use Simon Tatham's Puzzles on your eReader with this new KoBox/X11 subsystem extension. Uses
https://www.chiark.greenend.org.uk/~sgtatham/puzzles/ software.
Available here:
http://23.163.0.39/bundles/kobox/extensions/
Connect USB cable, go in KoBox settings -> Export extensions storage then drag-and-drop
puzzles.isa and
puzzles.isa.dgst files in the drive from your computer.
You can launch it by going in KoBox apps -> Puzzles. Then, a dialog will pop up and ask you the puzzle you want to do. If you want to return to the main GUI, quit the puzzle and click the "Cancel" button of the dialog.
Enjoy!