Microsoft on Monday officially announced the details of Windows Phone 7 Series' app store, user interface and software development kit at the MIX10 developer conference at Las Vegas.

Microsoft previewed free development tools for Windows Phone 7 Series such as Silverlight, a Windows Phone 7 Series add-in, XNA Game Studio 4.0 and Microsoft Visual Studio 2010 Express for Windows Phone.

The Silverlight and XNA, which will be employed by Windows Phone 7 Series, are expected to play vital roles for third-party software developers.

Silverlight will be used as the coding toolkit for sophisticated internet applications. The apps will support hardware-accelerated video, accelerometers, multi-touch, Microsoft Notification Service and Microsoft Location Service.

Speaking on the topic, Charlie Kindel from Microsoft said, "I think we've been very clear since we first started talking about [Windows Phone 7 Series] that it represents a sea change for Microsoft."

XNA, which is a set of programming tools, makes it easier for developers to design games for multiple Microsoft platforms such as Windows XP, Windows Vista, Windows 7 and Xbox 360.