Mathdoku (also known as KenDoku, Calcudoku or KenKen®) is a type of arithmetic/logic puzzle invented by Japanese math teacher Tetsuya Miyamoto. The puzzles were intended to be an instruction-free method of training the brain.
As in sudoku, the goal of each puzzle is to fill an NxN grid with digits (1 to N); such that...
・No digit appears more than once in any row or column.
・The numbers contained in each cage (outlined group of cells) produce a certain "target" number, when combined using the math operation provided.
・Digits may be repeated within a cage, as long as they arent in the same row or column.
This lite version of the game supports 5 modes of play on iPhone, iPod Touch & iPad. Oh...and the puzzles are auto generated...so no in-app-purchases necessary!