Really lovely art!
Could not really figure out the mechanics. Got stuck on the tutorial and had to restart the application.
An in-game tutorial is great, but tricky to pull off in a clear way. Could use some UI highlighting and movement. Also when numbers change during the game.
Some additional illustrated basic instructions on the game page wouldn't hurt either. Explaining the different numbers on the screen.
I'll try to give it another go a day when i have more brain power remaining :)