Colorku on the full 9 by 9 grid swaps the numbers for nine bold shapes: a circle, a square, a triangle and more. It follows the rules of Sudoku exactly. Each shape is drawn with a heavy outline, so it is told apart by form and not by colour alone, and each key on the pad carries a small number. Easy is the free daily Colorku, and members will be able to play Medium and Hard as well.