Apple shows off iPhone OS 4.0

Some iPhone users will soon be able to run multiple apps at once

Apple has provided the first glimpse into its upcoming iPhone firmware update, which promises upwards of 100 new features for the iPhone and iPod touch devices.

Headlining the new features is multitasking capabilities. Long rumoured to be in the works, the feature will allow users to run multiple third-party apps at the same time.

The feature will not be available to all iPhone versions, however. Apple said that iPhone 3GS and iPod touch models released before late 2009 will not be able to multitask.

Apple also plans to overhaul the iPhone OS interface, allowing users to create folder directories for applications and organise email messages as conversation threads.

Following in the footsteps of the recently-released iPad, Apple is adding an e-book reader to the iPhone. Like the iPad, the reader application will allow users to purchase books through Apple's iBooks service.

Developers also got some welcome news with the promise of 1,500 new application programming interfaces, as well as iAds, a new platform which will allow developers to embed full-screen video, image and interactive display advertisements into their applications without the need to launch a browser window.

Apple said that the iPhone OS 4.0 build will be released to the general public later this summer, and a version for the iPad in the autumn.

Those registered with the iPhone Developer Program can obtain beta versions of the OS through Apple's developer web site.