Fill the grid so that every row, every column and every 3×3 box contains the digits 1 to 9 once each. Tap a square, then tap a number. Digits that clash with another in the same row, column or box turn red. Every puzzle has exactly one solution.

Everyone gets the same puzzle each day, so you can compare times with friends. Your progress is saved on your device, so you can come back to it later.