← Patmos Software

Shikaku

Divide the grid into rectangles. Every rectangle holds exactly one number, and that number is how many squares it covers. Cover the whole grid and the puzzle is solved.

That is the entire rulebook. There is no tutorial to sit through — the first boards are small enough that the answer is nearly visible, and by level ten you are genuinely working.

Download on the App Store Support

iPhone · iOS 17 or later · Free to level 40, then one payment

A Shikaku board part-solved in the Midnight theme, with numbered clues and drawn rectangles. The same game in the Forest and Brass theme. A completed puzzle showing the score for a clean solve.

Midnight, Forest & Brass, and a finished board.

One answer, always

Every board is checked for a unique solution before you ever see it. There is never a moment where you have to guess and hope. Anything you can work out, you can prove.

It catches the move that broke it

A rectangle can obey every rule and still make the rest of the puzzle impossible — leaving a number with nowhere to go, or a square nothing can reach. Shikaku tells you at the move that caused it, instead of letting you discover it twenty moves later with no idea where it went wrong.

Mistakes cost something. Fumbles do not.

Dragging across a rectangle you already placed is a mis-swipe, not an error, and costs nothing. Change your mind mid-drag, come back to where you started and let go — that cancels, free. Only real reasoning errors count against you. Three per puzzle.

Seven difficulties

Gentle, Easy, Medium, Hard, Expert, Master and Grandmaster. The hard tiers are not simply bigger boards — a Grandmaster puzzle has fewer, larger rectangles and far less that can be read off at a glance. It is close to pure deduction.

A new puzzle every day

The Daily Challenge is free forever, with or without the full game. Keep it up for seven days running and you earn hints. Every player gets the same board, worked out from the date, with no server involved.

Your progress is yours

Put it down mid-puzzle and it is exactly where you left it. Everything lives on your device. Nothing is collected, nothing is sent anywhere, and there is no account to make.

What is free and what is not

 FreeFull game
Levels1–40Unlimited
DifficultiesUp to Hard+ Expert, Master, Grandmaster
ThemesMidnightAll three
Daily ChallengeAlwaysAlways

One payment unlocks the rest. No subscription, no adverts, no lives, no timers, and nothing to wait for.

Why there are no lives: there used to be. The game turned out to be too fair to charge anyone, so the business model changed instead of the game — the whole story is here.