WatchSudoku

Full 9x9 Sudoku controlled via touch and digital crown.
Touch control is intuitiv to understand. Change the number with the digital crown.
Sudoku is a number puzzle where the objective is to fill every row, column and box (3x3 grid) with the numbers from 1-9. Each unit (row, column or box) must have each number exactly once. The game starts with a number of fields pre-filled. Your objective is to fill the rest of the fields without breaking the constraints that each number can only be once in each row, column and box.