Sudoku for Android

Sudoku (originally called Number Place) is a logic-based, combinatorial number-placement puzzle. The objective is to fill a 9x9 grid with digits so that each column, each row, and each of the nine 3x3 sub-grids that compose the grid contains all of the digits from 1 to 9.

FEATURES:

- four different difficulties

- hundreds of puzzles for each difficulty

- auto-save your progress for each puzzle

- unlimited undo/redo

- auto-fill drafts

- hint system for beginners

- color input system for experts

- clean interface and smooth controls

- google play games achievements

- phones and tablets support

HELPFUL FEATURES (optional):

- selection modes: select first or number first

- pencil modes: automatic or manual

- keyboard configuration: three rows, two rows, one row

- direction highlight: vertical and horizontal highlight

- number finder: highlight all occurrences of a number

- number counter: show a counter for each number

- rule violations: game rule warnings highlight

- keyboard highlight: shown if number count is correct or incorrect

- multiple color input (advanced): use different colors to place numbers

- automatic error detection: show errors automatically

- permanent auto-fill: continuously fill all the drafts

- bigger numbers: large font for better visualization