After nearly 400 puzzles, there is still very little challenge to any of them. You have to watch one ad for every two puzzles completed. After five puzzles you're given a "gift", but to claim your "gift", you must watch another ad... AND half the time after watching the ad I get an error message saying no ads are available and I have to watch yet another ad to get the gift! You spend more time watching ads than you do solving puzzles! A waste of time! I'm Uninstalling it!