Unreliable Undo Function – KenKen Classic Review

Many puzzles require testing “guesses” to see if they play out or not. But the Undo function to get back to the “guessing point” fails often, leaving no option but to essentially start the puzzle over. Failures occur very often if the app is switched out for another app (eg a phone call), even for a moment. Sometimes it happens for no apparent reason at all.
Review by Condorr on KenKen Classic.