This was a small piece of design work I did for myself in Photoshop during last year to entertain myself during a powercut. All background wallpaper artwork shown was not created by myself, they are from wallpaper packs I had on my iPod touch previously.
What makes this design individual from other mobile OSs is the layout. The small bar on the right hand side holds all of your apps, you can use your finger to scroll up and down the apps. After an app has been highlighted, a full-screen preview image of the app will appear as a semi-transparent wallpaper, including optional preview audio for snippets of game soundtracks. If you tap the little cogs at the bottom of the bar, you will be able to access toggles such as rotation lock, wifi, song selection/cover art etc. The lock screen goes by a similar design and has a custom wallpaper option, music controls, notifications (slides out from the right hand side) and a page-curl to unlock. This design is highly inspired by the classic PSP XMB menu.