Unlike many other similar games where you have to find the differences between two seemingly identical images, here the differences are smaller than usual. They can be between 50 and 100 pixels, which is equivalent to a few millimeters of screen real estate; that is not always immediately visible. But there are also big discrepancies, so you won't have to break your vision on each level. To highlight how well you're doing, the system shows how many you've already found out of how many in total: you see the stars above the playing field, marked each time you find something. Playing with the sound on is a bit relaxing, but if you don't like the music and sounds of hit finds, you can turn them off.