Sudoku Touch started out as a design exercise. The brief was to create a Sudoku game for iPad using handwriting recognition as the input method.
Essentially, it was a way to explore how handwriting recognition could be used on a touch screen device. The solution I designed is so elegant we decided to make the game anyway, and so Sudoku Touch came to be.
A Sudoku game is fairly simple and contained within a 9 × 9 grid, so doesn’t require a lot of screens. I included a difficulty select menu, a game screen, pause and options menu and an end game screen. Many Sudoku players also like to create notes in each square for possible answers.
Players simply want to select a difficulty level to suit their tastes and start playing. Some options are required; every game is expected to be able to be paused and players who are less competitive will want to be able to disable the timer clock. Novice players also like to be shown when they've entered an incorrect answer.
I explored a few different ideas with special areas of the screen dedicated to input. Each positioning of the input area in different parts of the screen required various layout compromises. A sudoku game is a square and doesn’t leave a lot of space for an input area.
After cycling through various interactions I hit on the idea of using the entire screen for handwriting input. It was a simple idea that allowed the game board to take up the whole screen. Every other interaction in the game is a simple tap or double tap which don’t clash with the handwriting gestures.
I created various prototypes in keynote to explore different methods for creating and deleting notes. We settled on a double tap to show and hide notes for each cell. Drawing a number with a note selected will add that number to the note and drawing it again will remove it.
For deleting all notes in a cell I considered a scrubbing ‘z’ gesture, however a two finger swipe down is quicker and more accurate.
My research revealed that the original version of Sudoku was created by a the French newspaper Le Siècle, however modern Sudoku was popularised in Japan and the name is also Japanese. I choose to use a rich visual style that evoked a zen garden.
After searching through many calligraphic typefaces I chose Azuki because it strongly evokes Japanese brush calligraphy.
While I created animations for the menus these weren’t included in the final game to keep the file size down, since it would mean separating graphics into individual components rather than individual background images.