KenKen Classic, developed by KenKen Puzzle LLC, is an addictive and entertaining brain-training puzzle game that is frequently described as "sudoku on steroids." It is perfect for people who love other brain games such as sudoku, jigsaw puzzles, crossword puzzles, and word search puzzles. This is the original KenKen app created by acclaimed Japanese mathematics educator Tetsuya Miyamoto.

KenKen Classic features virtually unlimited puzzles ranging from 3x3 to 9x9 grids and from easy to expert levels. The game includes 50 free fun math puzzles of every size and difficulty level, and unlimited free 3x3 size puzzles to learn from and enjoy. You can select the size, difficulty level, and operations to challenge yourself. The game also offers a variety of color schemes and music, and you can even set your own music to play in the background.

KenKen Classic has three input modes for digits and notes, along with great extra features such as hints, check, undo, redo, reset, pause, and timer. The game also has online leaderboards, allowing you to compete against other players. You can post your results directly to Twitter and email results to invite friends.

Overall, KenKen Classic is an outstanding puzzle game that will keep your mind sharp and entertained for hours.