Sudoku is
a logic based puzzle game about number combinations. The goal is to fill a 9x9
grid with digits such that each column, each row, and each of the nine 3×3
sub-grids that compose the grid (also called "boxes",
"blocks", "regions", or "sub-squares") contains
all of the digits from 1 to 9. In each game the game starts with a partially
completed grid, which for a well-posed puzzle has a unique solution.
Download link: https://play.google.com/store/apps/details?id=asl.sudoku