Over the summer, I was quite busy with a startup company (Spooncow Entertainment) that my business partner and I were working on. The company would focus on creating small and fun puzzle based games for the iPhone and iPod Touch. The project that we had been working on for around 2 and a half months or so to test the waters was finally submitted to Apple on May 06. The below are some of the screenshots from the completed game that I had fully designed.
You can take a look at it on the app store here: [link]
Basically there is no fixed place you have to put the "slices" in, but you get more points if they are matched with the background piece. This is at the individual slice level. If an entire pizza is completed with all pieces matched according to their background, then you get a major bonus. This is much harder than it looks (and harder than another popular game by the name Frenzic) since gameplay speed and variability of the pieces both type wise and position wise make it harder to keep track of the background + individual corresponding pieces as they come in.
You also get "throw-outs" indicated by the 3 led lights on the main plate (inactive in the pic). Each time a perfect pizza (correct matching of slices to background) is made, a single throw-out light goes on (with a maximum of 3 lights), and when this is active tapping on the centre plate causes the slice to change, so it's possible to get out of a tricky situation if enough throw-outs are collected. The game UI was designed entirely in Photoshop and took a span of several months to finish.