Play Sudoku and Win Amazon.com Gift Cards*! This is a classic Sudoku puzzle app. By completing puzzles you get a chance to win Amazon.com Gift Cards* sweepstakes. If you win, the gift code will appear on your screen immediately. Copy the gift code and use it now! What is Sudoku? Sudoku is a puzzle game in which the numbers 1 to 9 are placed in 9x9 (81 squares) squares separated by 3x3 blocks. Playing is easy! 1. Enter one of the numbers 1-9 in the empty squares. 2. The same number cannot be placed twice in a row, column, or block of 3×3 squares surrounded by bold lines. The sweepstakes in this app is conducted independently by the Company and is in no way affiliated with Apple Inc. *Restrictions apply, see amazon.com/gc-legal