Sorry to ask a bit late and probably not in the best topic, but I have a request. I solved Sudoku City online and found the 'Undo' button quite useful. Unfortunately I clicked on it too many times when solving the Product Sudoku and I got lost which correct numbers I have removed (I was too tired :( ).
Would it be possible to add a 'Redo' button as well or it would be an advantage for online solvers because offline solvers can't 'redo' erased numbers from the 'memory' of the paper?

Edited by wicktroll 2011-08-17 12:27 AM

I'm not sure if "redo" feature is a good idea. Like you, I've a feeling that it will be more advantage to online players.

You should be using different colors, if you bifurcate while solving online.