Apple has revealed that its next iPhone update will include more than just the expected addition of a software development kit (SDK).

The company said that a host of enterprise-minded features and an application store will be added to the iPhone 2.0 software release.

Developers and certain enterprise customers will be able to download the beta release immediately. All other users will have to wait until June.

Apple unveiled plans to release an iPhone SDK in October when chief executive Steve Jobs issued an open letter to customers promising to have the kit in the hands of developers by March 2008.

The SDK will allow developers to create applications which run natively on the iPhone. Apple has previously allowed only web-based applications, citing privacy and compatibility concerns.

Some developers have already created native applications for the iPhone, although the installation of such software is not supported by Apple and requires the user to run a special 'jailbreak' procedure on the handset.

The SDK will include APIs for the iPhone's Core OS, Core Services, Media and Cocoa Touch software components.

Developers will be able to sell their software to users via Apple's new iPhone App Store which will allow users to download the software directly to the iPhone or iPod Touch.

Apple said that developers can set their own prices for applications sold on the store, and that the company would take a 30 per cent commission. The figure is similar to the prices Apple reportedly pays record labels for songs sold via iTunes.

"We are excited about creating a vibrant third-party developer community with potentially thousands of native applications for iPhone and iPod Touch," said Jobs.

"The iPhone's enterprise features, combined with its revolutionary multi-touch user interface and advanced software architecture, provide the best user experience and the most advanced software platform ever for a mobile device."

Apple plans to add support for Exchange 2003 and 2007 servers into the update, and has licensed Microsoft's Exchange ActiveSync, which allows the iPhone to support push email as well as automatic calendar and address book updates.

The iPhone will support Exchange's remote wipe, password policies and auto discover security features.

The 2.0 update will also allow the iPhone to support Cisco's IPSec encryption protocol and the WPA2 wireless protocol, ensuring secure transmission of data to and from the device.