The board consist of 9 squares, arranged in a 3x3 grid; any row or column can be cyclicly permuted by swiping on it. The aim is to get the pieces arranged as 1,2,3,4,5,6,7,8,9.
Each given instance is solvable because each puzzle is created by running moves in reverse; this does not mean the solution I have is in any way optimal of course! I also do not know if all possible initial states can be solved. I have a vague suspicion that it is impossible to switch two pieces whilst leaving the remaining stones in place (there is a half remembered parity argument somewhere)
Anyhow, feel free to have a go of the game here.