Sudoku 4ever Free is an Android puzzle game developed by 1gravity. It offers an unlimited number of puzzles with eight difficulty levels, making it an ideal game for both beginners and expert players. The game features eight different Sudoku variants, including Classic, Jigsaw puzzles (aka Squiggly), Asterisk, Centerdot, Color, Hyper, Percent, and X-Sudokus.

Players can choose from six input methods, including digit first, cell first, mixed, Andoku cell first, Andoku digit first, and popup. The game also supports pencil marks with auto-set or auto-erase, persistent undo/redo, and auto-save. Other features of the game include bookmarks, highlighting of selected digits and pencil marks, highlighting of completed digits, and highlighting of incorrect digits.

Sudoku 4ever Free also offers advanced hint functionality and analysis functionality to rate the difficulty of a Sudoku puzzle and to get a detailed list of required solving techniques. The game statistics feature shows fastest, average, slowest times and total time played for each difficulty level. The app is extremely configurable and supports portrait and landscape mode, all screen types and sizes, touch screen, keyboard, and trackball. It's a great app for Sudoku enthusiasts and comes with unobtrusive ads in the free version.