Android UI Design

"Smaller mobile devices such as PDAs and smartphones typically use the WIMP elements with different unifying metaphors, due to constraints in space and available input devices. Applications for which WIMP is not well suited may use newer interaction techniques, collectively named as post-WIMP user interfaces.
As of 2011, some touch-screen-based operating systems such as Apple's iOS (iPhone) and Android use the class of GUIs named post-WIMP. These support styles of interaction using more than one finger in contact with a display, which allows actions such as pinching and rotating, which are unsupported by one pointer and mouse." [Graphical user interface. Wikipedia]
"In computing post-WIMP comprises work on user interfaces, mostly graphical user interfaces, which attempt to go beyond the paradigm of windows, icons, menus and a pointing device, i.e. WIMP interfaces. ...
However WIMP interfaces are not optimal for working with complex tasks such as computer-aided design, working on large amounts of data simultaneously, or interactive games. WIMPs are usually pixel-hungry, so given limited screen real estate they can distract attention from the task at hand. Thus, custom interfaces can better encapsulate workspaces, actions, and objects for specific complex tasks. Applications for which WIMP is not well suited include those requiring continuous input signals, showing 3D models, or simply portraying an interaction for which there is no defined standard widget.
Interfaces based on these considerations, now called "post-WIMP", have made their way to the general public. Examples include the interface of the classic MP3 player iPod and a bank's automated teller machine screen." [Post-WIMP. Wikipedia]
The example "iPhone OS (iOS) graphic user interface (GUI) - Activity indicator view" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Graphic User Interface solution from the Software Development area of ConceptDraw Solution Park.