Sudoku Uno is an elegant implementation of the popular Sudoku game. Its pleasing interface wraps an extensive feature set that makes Sudoku Uno stand out of the crowd. Sudoku Uno provides an almost infinite number of Sudoku games categorized in 3 levels of difficulty. Its powerful engine is also able to provide intelligent hints: the engine may explain the reasoning behind the hint. Features: Three levels of difficulty: easy, medium, hard Difficulty levels are determined by techniques to master, not by number of givens Unlimited number of Sudoku games Green & red pencil notes Optional automatic pencil notes (*) Optional blocking of erroneous entries Intelligent hints with explanations High scores (*) Sudoku Uno may help you by blocking digits which are obviously no longer available and by setting positive markers for the remaining ones. You should further narrow down the possible digits by setting negative markers.