Under rating threshold (hideshow)
Like dedfink said, the idea of moving images for finding the differences is not bad, but the game should tell people what they have to do next. Was not too hard to figure it out on the second try but once you know it, the game is too short. Also should change the order of the pictures once you restart at level 1. The order was exactly the same, so it wasn't a challenge to replay.
Under rating threshold (hideshow)
Needs an introduction, something before each stage to tell you what your suppose to be doing. I'm still not sure what the third stage is suppose to be... Other than that pretty fun. It's a cool idea to have the difference stage moving, makes it much more difficult.