Sudoku 2020 app for iPhone and iPad

Sudoku is a game of logic, problem solving and spotting patterns – it’s a true “brain game” that helps stimulate people’s cognitive abilities and gives the satisfaction of accomplishing a difficult puzzle.

Cognitive psychologists and neuroscientists have found that memory starts to decline as early as your 20s. Meaning that, despite your collegiate environment, many of you are probably already starting to slip. The upside? According to research done at Trinity College in Dublin, mental stimulation over puzzles like crosswords and Sudokus can help ward off decline in brain function.

History of Sudoku game:
Sudoku originally called Number Place is a logic-based, combinatorial number-placement puzzle.
The objective is to fill a 9×9 grid with digits so that each column, each row, and each of the nine 3×3 subgrids that compose the grid (also called "boxes", "blocks", or "regions") contains all of the digits from 1 to 9. The puzzle setter provides a partially completed grid, which for a well-posed puzzle has a single solution.

Completed games are always a type of Latin square with an additional constraint on the contents of individual regions. For example, the same single integer may not appear twice in the same row, column, or any of the nine 3×3 subregions of the 9x9 playing board.
French newspapers featured variations of the puzzles in the 19th century, and the puzzle has appeared since 1979 in puzzle books under the name Number Place.

However, the modern Sudoku only started to become mainstream in 1986 by the Japanese puzzle company Nikoli, under the name Sudoku, meaning "single number". It first appeared in a US newspaper and then The Times (London) in 2004, from the efforts of Wayne Gould, who devised a computer program to rapidly produce distinct puzzles.