I'm glad there's the 5-box (Samurai) sudoku in there.
BUT EyraT is right about being unable to click away from the upper left corner to enter a value sometimes.
AND nearly every time there are multiple solutions. I don't know how to fix that, but it's been done.
Keep improving the presentation too, please.

The regular sudoku is alright. The Samurai Sudoku made my day, or to be more accurate, my 2 hours when I was trying to fall asleep. wonderful. Even if it is just Sudoku. You should consider programming a Ken Ken game, less often heard of, I'm sure you'd get some good results.

I find it fairly challenging but the idea of the 5 squares detracts from this. There is also a bug where if you input possible numbers then remove them to put the correct number in the box it won't let you. Overall it's an ok game but there isn't anything really unique about it. It's still just another sudoku game.