iPhone - OS X

The iPhone will run an optimized version of the Mac OS X operating system (without unnecessary components).  The differences between the operating system (OS X) running on Macs and the iPhone have not been officially explained.

Apple intends to offer a smooth method for updating the iPhone's operating system, in a similar fashion to the way that Mac OS X and iPods are updated.

OS X is expected to take up considerably less than 500 MB.  It will be capable of supporting as-yet undetermined bundled and future 1st and 3rd-party applications, the latter of which are currently limited to a "controlled environment".

The iPhone's version of OS X includes the software component "Core Animation" which is responsible for the smooth animations used in its user interface.

Widgets, similar to the ones available in Mac OS X v10.4's Dashboard, are also included on the iPhone. The examples given in the Macworld 2007 keynote were Stocks and Weather widgets.