New Apple iPad User Interface Elements and Behaviors
In iPhone OS 3.2, UIKit includes some new UI elements and defines new behaviors for a few elements that are available in earlier versions:
Split view. You can use this iPad-only element to display more than one view onscreen at a time, such as to present data in a master-detail or source list–style arrangement. The split view is a common organizational element in iPad applications because it helps flatten the information hierarchy.
Popover. You can use this iPad-only view to temporarily display additional information, controls, or choices related to content in the main view. The main benefit of the popover is that ...