I couldn't stop playing this game. If someone described it to me I would think it was really tedious and boring but somehow I found it both relaxing and addictive. Really unique concept and engaging gameplay, even if I don't understand why it is so.
One minor nitpick is that the challenges tab should start with available and uncompleted challenges rather than making it necessary for players to scroll down to find the available challenges. That aside, I really enjoyed this game and I think you're a wizard.