The iPhone OS software is a mobile operating system that is the backbone of several products made by Apple Inc. These include the iPod Touch, the iPad and the iPhone. The iPhone OS 4.0 was unveiled on April 8, 2010. The OS upgrade was available to public Apple Developers shortly after the event while the public will be able to access the update in the Summer of 2010. Apple iPhone OS 4 will be the latest version of the operating system, which first made its appearance in January 2007 at the Macworld Conference and Expo.http://www.macworld.com/article/54769/2007/01/iphone.html

Existing developers who are already enrolled in the iPhone Developer Program can download the updated iPhone OS at developer.apple.com.http://www.apple.com/pr/library/2010/04/08iphoneos.html

iPhone and iPod Touch users will be able to download the iPhone OS 4 in the Summer of 2010.http://www.apple.com/pr/library/2010/04/08iphoneos.html

A version of the iPhone OS 4 will be available for the iPad in the Fall of 2010.http://www.apple.com/pr/library/2010/04/08iphoneos.html

The iPhone OS 4.0 will be the newest instalment of the primary iPhone operating system, supplanting the iPhone OS 3.0 Final.

For a full list of features and functions, please see:

New iPhone Features

Among the many new features which are expected to be showcased on April 8, 2010, will be its ability to mutli-task and to run multiple iPhone apps in the background. Current versions of the iPhone OS do permit limited multi-tasking, but they are confined to apps which come bundled with the iPhone unit.http://www.appleinsider.com/articles/10/03/11/apples_iphone_4_0_software_to_deliver_multitasking_support.html Third party apps could not be multi-tasked.

It is expected, that in focusing on this new ability to multi-task all apps, new security features to prevent malware from running in the background and intuitive navigation between open apps will also be presented.