Nice interface!!!!
loved the way u can solve them, so much easier to do it digitally than on paper just like sudoku games!!!! i painstakingly spent 30 min on the easiest one and finally got it..........But i dont know if i did it properly, a message of some sort to let you know if you are right would be much much appreciated. I know every puzzle has one and only one solution so you can check yourself if ur right, but still.
just improve that bit and you have a good puzzle here, maybe even a slight hint system???