Nonogram — Picross

Nonograms — also sold as Picross, Griddlers and Hanjie — are picture-logic puzzles that emerged in Japan in the late 1980s, independently invented by designer Non Ishida and puzzle author Tetsuya Nishio. The numbers beside each row and above each column tell you the lengths of the runs of filled cells in that line, in order, with at least one empty cell between runs. Deduce every line correctly and a hidden pixel picture appears.

This version offers 5×5, 10×10 and 15×15 grids, and every puzzle is verified by a built-in line-logic solver to have exactly one solution — so there is always a next move you can prove, and you never have to gamble. Many boards reveal a named picture from a curated gallery. If you fill a cell that should be empty, the game marks it with an X for you and docks one of your three hearts; an optional strict mode resets the board when all three are gone.

Alongside free play there is a shared Daily puzzle whose grid size rotates through the week, with a streak counter, a countdown to the next one, and a shareable result. A timer tracks every solve and your best time is saved separately for each size and for the daily, so speedrunning your favourite grid is a genuine progression. Everything is stored on your device — no account needed.