How to play
Statedoku is a daily geography puzzle. You fill a 3×3 grid with US states. Every row and every column carries a label, something like Borders Mexico or Name ends in A, and each state you place has to satisfy its row label and its column label at once. Nine cells, no state twice, three mistakes allowed.
Reading the grid
Row labels run down the left edge, column labels across the top. A cell sits where two of them cross, and wants a state that answers both.
Say the row reads Borders Mexico and the column reads Pacific coast. Four states border Mexico: Arizona, California, New Mexico and Texas. Five have a Pacific coastline: Alaska, California, Hawaii, Oregon and Washington. Only California is on both lists, so California is what that cell wants.
Tap a cell and a picker opens showing its two labels side by side, so you never have to trace back to the edges. Type at least four letters of a state's name to see matches. Abbreviations are not searched, so CA will not surface California.
What counts as correct
Any state that satisfies both labels is accepted. Not one particular intended answer, any of them.
Keep the row at Borders Mexico and switch the column to Name ends in A. Arizona fits. California fits. Place either and the cell turns green. Earlier versions checked your pick against one stored solution and refused correct states that did not match. That check is gone. You win when all nine cells hold states satisfying their labels and all nine are different, and there is no answer key beyond that.
Changing your mind
That flexibility has a consequence. Since both Arizona and California are accepted in the ends in A cell, you can legitimately spend a state another cell needed. Put California there and the Pacific coast cell is left with nothing, because California was its only answer.
So filled cells are not locked. Tap one and the picker reopens with a Clear this cell button at the bottom. Clearing empties the cell and puts that state back in circulation. It costs nothing, and you can do it as often as you like.
Mistakes
You get three a day, shown as three dots above the grid. A mistake is one of exactly two things: the state fails one or both of its labels, or it is already sitting elsewhere in the grid. Placing a valid answer never costs a mistake, even when it proves a poor strategic choice. Clearing a cell costs nothing, and neither does putting the same state back.
When a pick fails, the cell shakes red, the state is removed, and one dot fills in. After the third, the puzzle ends and the answers appear, listing every state that would have worked in each cell. The picker greys out states already on the board, so duplicates are hard to hit by accident.
Playing it well
Fill the most constrained cells first. Before typing anything, estimate how many states could go in each cell. Borders Mexico crossed with Pacific coast has one answer. Crossed with Name ends in A it has two. Fill the single answer cell first and the other still has Arizona waiting. Do it the other way round and you may hand California to the cell that could have managed without it. Left to right, top to bottom is the worst possible order.
Let the narrow label do the work. Most cells pair one tight label with a loose one. Landlocked matches twenty states and Name ends in A twenty-one, while Borders Mexico matches four. Start from the short list and filter it with the other label rather than holding both in your head at once.
Skip instead of guessing. If two candidates both look plausible, leave the cell empty and come back once the states around it are committed. And when a cell has no valid state left, the answer it needs is almost always parked in another cell. Find it and clear that one rather than guessing.
Every day, and sharing
A new grid arrives each day at midnight, and everyone playing that date gets the same nine cells. Progress saves in your browser, so you can close the tab and pick the grid up later on that device. Solve it and you can share a spoiler-free emoji grid. Some days also hide a Golden State, a state in the solution that satisfies all three column labels at once. Place it for a one-time bonus and a 🌟 on your result.