ZieWizard's Mini Sudoku app for iPhone and iPad

Mini Sudoku is a Sudoku puzzle maker based on a simplified sixteen cell board. Considerably easier to solve than the full blown standard Sudoku it will delight children and adults alike, Instead of the nine cells per row, column, and quadrant of standard Sudoku, Mini Sudoku only has four cells per row, column, and quadrant. Solving the Mini Sudoku puzzles requires less time to solve but with similar challenges. By simplifying the challenge, Mini Sudoku allows for shorter solution times and gives new users a chance to become acquainted with solution methods without experiencing the frustration of the standard Sudoku. Experienced Sudoku fans may also enjoy Mini Sudoku as it provides quick challenges and solution rewards.
The use of emoticon figures instead of numbers will delight children as well as adults.

The principles to solve Mini Sudoku Basic Level puzzle are basically the same as in standard Sudoku. But instead of dealing with nine cells is each row, column, and quadrant, there are only four. Lets briefly review the rules: All rows, columns, and quadrants must have cells filled with one of the figures without duplicates just as shown in the caption above.

Mini Sudoku also includes a Super Level which adds an additional challenge to solving the puzzles. The rules not only require the rows, columns, and quadrants be filled with an emoticon figure without duplicates, but also the diagonals that run across from corner to corner in either direction