Improving the UX of Sokoban on a touchscreen using a simple solver.

Tap on an empty tile to move the player there -- if possible! -- without disturbing any crates.

Tap on a crate and then an empty tile to move the crate there -- again, if possible! -- without disturbing any _other_ crates.

All integrated with the infinite undo.

Now I can spend less time juggling arrow buttons on a touchscreen and more time thinking about the puzzle itself: which crate to move next, and where to put it.

Comments gratefully appreciated. Please send them to me by any method of your choice and I'll include them here.