Apple today previewed the iPhone 2.0 software, which it will release in June.

The company also announced the immediate availability of a beta release of the software to selected developers and enterprise customers.

The iPhone 2.0 beta release includes both the iPhone Software Development Kit (SDK) as well as new enterprise features such as support for Microsoft Exchange ActiveSync to provide secure, over-the-air push email, contacts and calendars as well as remote wipe, and the addition of Cisco IPsec VPN for encrypted access to private corporate networks.

“We’re excited about creating a vibrant third party developer community with potentially thousands of native applications for iPhone and iPod touch,” said Steve Jobs, Apple’s CEO. “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.”

The iPhone SDK provides developers with a set of Application Programming Interfaces (APIs) and tools to create innovative applications for iPhone and iPod touch. Starting today, anyone can download the beta iPhone SDK for free and run the iPhone Simulator on their Mac.

Apple today also introduced its new iPhone Developer Program, giving developers everything they need to create native applications, and the new App Store, for wireless delivery of applications to iPhone and iPod touch users.

As explained elsewhere on Macworld UK, the iPhone SDK includes programming interfaces for Core OS, Core Services, Media and Cocoa Touch technologies. It also lets developers create applications that use the iPhone’s Multi-Touch user interface, animation technology, large storage, built-in three-axis accelerometer and geographical location technology.

Apple has licensed Exchange ActiveSync from Microsoft and is building it into the iPhone, so that iPhone will connect out-of-the-box to Microsoft Exchange Servers 2003 and 2007 for secure over-the-air push email, contacts, calendars and global address lists. Built-in Exchange ActiveSync support also enables security features such as remote wipe, password policies and auto-discovery. The iPhone 2.0 software supports Cisco IPsec VPN to ensure the highest level of IP-based encryption available for transmission of sensitive corporate data, as well as the ability to authenticate using digital certificates or password-based, multi-factor authentication. The addition of WPA2 Enterprise with 802.1x authentication enables enterprise customers to deploy iPhone and iPod touch with the latest standards for protection of WiFi networks.

The iPhone 2.0 software provides a configuration utility that allows IT administrators to easily and quickly set up many iPhones.

The iPhone 2.0 software release will contain the App Store, a new application that lets users browse, search, purchase and wirelessly download third party applications directly onto their iPhone or iPod touch. Developers set the price for their applications - including free - and retain 70 per cent of all sales revenues.

Enterprise customers will be able to create a secure, private page on the App Store accessible only by their employees. Apple will cover all credit card, web hosting, infrastructure and DRM costs associated with offering applications on the App Store. Third party iPhone and iPod touch applications must be approved by Apple and will be available exclusively through the App Store.

The iPhone SDK also offers advanced tools for creating native iPhone and iPod touch applications including: Xcode for source code editing, project management and graphical debugging; Interface Builder with drag and drop interface creation and live preview; Instruments to monitor and optimise iPhone application performance in real time; and the iPhone Simulator to run and debug applications.

During the beta iPhone SDK program, a limited number of developers will be accepted into Apple’s new iPhone Developer Program and offered the ability to get code onto iPhones for testing. The Standard Program costs $99 per year and gives members an iPhone SDK and development tools; access to pre-release iPhone software; technical support; the ability to get code onto iPhones for testing; and distribution of applications via the new App Store. The Enterprise Program costs $299 (US) per year.

In addition to these new iPhone network and security features, the beta iPhone 2.0 software provides several new Mail features such as the ability to view PowerPoint attachments, in addition to Word and Excel, as well as the ability to mass delete and move email messages.

Apple plans to release the final iPhone 2.0 software, including the iPhone SDK and new enterprise features, as a free software update for all iPhone customers by the end of June. iPod touch users will be required to purchase the software update.

The free beta iPhone SDK is available immediately worldwide and can be downloaded at developer.apple.com/iphone/program. The iPhone Developer Program will initially be available in the US and will expand to other countries in the coming months.

Apple is accepting applications beginning today from enterprise customers who would like to join the private iPhone Enterprise Beta Program.