Nonograms Katana

Nonograms Katana is a "paint by number" style game, where the player must recreate a picture in a grid by filling in cells, with the help of clues which tell about the lengths of groups of filled cells in each row and column.

The game comes with several hundred built-in puzzles. Apart from filling in cells, the player can mark cells with crosses or dots. Puzzles can be zoomed in or out, and moved around. The player can ask for up to 15 hints, each hint uncovering one filled cell. There is an auto-fill option, where filling in all the cells in a row or column marks all remaining cells as empty.

The paid "VIP" version of the game (bought with in-app purchases) comes with no ads, and the option to show the answer to a puzzle instantly.