Apple's patent filing mentions how some mobile communications devices can end up being swamped by buttons, or manufactured with buttons that control a number of different functions, or controlled with the use of a complex menu system. Apple noted that the use of these tools could result in the user having to memorize certain key sequences in order to store or retrieve information. In its filing, the tech giant also notes that some portable devices use a stylus to manage a list. But the problem with that is because the screen is designed to use the pinpoint edge of the stylus, it won't work with a thicker fingertip.
On the image below, provided courtesy of Patently Apple, you can see on the left, the diagram from Apple's patent filing that shows how the company envisioned displaying and managing a favorite contacts list on an iPhone. To the right is a screenshot of an Apple iPod Touch showing the patent in operation.
Another patent awarded to Apple, 8,090,767, covers how the portable hard drive capabilities of the Apple iPod Touch was eventually carried over to the Apple iPhone. The latter did not have the functionality of being used as a portable hard drive from the get go, which is something that the iPod Touch was capable of almost immediately upon its launch.
source: PatentlyApple via AppleInsider
Apple received a patent for the use of a finger and associated gestures to help display and manage a list on a mobile multifunction device