Entropy Game

This is a mind game where numbers are order Ascending in a grid cell.
last cell bottom left is empty.

pressing play will shuffle the numbers.You need to order them back.

Empty cell enable the user to reorder by swapping places between it and adjacent cells
(right,left,up, down)
simply touch a cell and drag it empty cell.
4 5 6 4 5 6 1 2 3
1 3 dragging 7 up----> 1 7 3 -.... eventually ----> 4 5 6
2 7 8 2 8 7 8