Sudoku is an example of a simple logic game that can be learned easily enough yet has the staying power to intrigue me to continue to play it. Dinko Osmankovic and the rest of the Sudoku Touch developers have created a version for ubuntu touch to fill those critical mundane moments of the day -- waiting for a train or having your morning coffee. Or perhaps if your like me, fighting insomnia (yikes!).
Apparently using the show hints button to play the entire game makes me a cheat.