Great, but...

The "undo" button is horrible! Sometimes it works fine, but mostly it will undo a random earlier move rather than the last one, or it will undo multiple moves at once; extremely frustrating!
Also, I agree with others that you should be able to double or triple tap a square instead of changing the tools at the bottom.
And it would be great if it didnt ask you if you wanted a hint at the start of every game.
I do love the game though!

Danielleighx about Nonogram - IQ Logic Pic Puzzle