I love nonogram type games. Nonogram Katana on Android has a lot of really cool user created puzzles.
I second Nonogram Katana! You can also play in the browser, but there’s seriously soooo many puzzles to do.
And if that isn’t enough of a game for some people, there’s a whole guild system of resources and upgrades. Not to mention a dungeon mini-RPG they added in the last year