Microsoft releases IE10 preview and Windows Phone 7.1 Mango beta

Microsoft has released the second platform preview of its Internet Explorer 10 browser and the beta build of its Windows Phone 7 upgrade, code-named Mango, with a new software developers kit (SDK.)

The browser includes a number of HTML5 improvements, including sandboxing security, drag-drop functions, CSS3 Positioned Floats and basic support for Forms.

A web worker tool is also included, which offloads JavaScript functions to a separate work area to boost browser frame rates by as much as a third.

"With platform previews, developers and technology enthusiasts can try out new technologies and provide feedback without any confusion about which technologies are site-ready and which are experimental," blogged Dean Hachamovitch, corporate vice president of Internet Explorer.

"This approach enables the technical community to work through safety issues before putting any consumers at risk, and minimises wasted effort re-writing consumer-facing sites."

The Mango beta build, along with the 7.1 beta2 SDK, will allow developers to start building and testing applications that use the new features of the operating system, such as the unified inbox, threaded messages, Windows Live Messenger support, double-sided Tiles and contact groups.

Mango will also contain much better integration with Office 365, officially launched yesterday, and will as other cloud applications. The mobile version of IE9 supports HTML5 and comes with Microsoft's free cloud-based storage service, SkyDrive.

The SDK will allow developers to build applications for both Windows Phone 7 and 7.1, and adds in tools for better multitasking and background operation of applications, access to sensor information from the gyroscope and compass, access to sockets using the TCP and UDP protocols and Visual Basic support in Silverlight and XNA Framework applications.