This game is intellectual puzzle.
The game is to sort the numbers.
This game have 8-puzzle and 15-puzzle.
8-puzzle or 15-puzzle is a sliding puzzle
that consists of a frame of numbered square
tiles in random order with one tile missing.
(supplementary explanation )
The 15-puzzle (also called Gem Puzzle,
Boss Puzzle, Game of Fifteen, Mystic Square and many others)
is a sliding puzzle that consists of a frame of numbered
square tiles in random order with one tile missing.
The puzzle also exists in other sizes, particularly the smaller 8-puzzle.
If the size is 3×3 tiles, the puzzle is called the 8-puzzle or 9-puzzle,
and if 4×4 tiles, the puzzle is called the 15-puzzle or 16-puzzle named,
respectively, for the number of tiles and the number of spaces.
The object of the puzzle is to place the tiles in order by making sliding moves
that use the empty space.
There are also other apps.