Tools and rules buffed for Microsoft's iPhone challenger

The final set of developer tools for Windows Phone 7 will drop on September 16 withp> what the company on Monday called "minor" breaking changes from the beta tools available now.

"These first six months have affirmed that a rich application platform based on the well understood Silverlight and XNA technologies, combined with great free tools based on Visual Studio 2010 and Expression Blend is the right approach for enabling developers and designers of all skill levels who are looking to capitalize on the opportunities presented by Windows Phone 7."

The company plans a limited beta of the Windows Phone Marketplace's submission and certification process in the coming weeks with "significant" changes to its developer portal following community feedback.

Clearly, Microsoft wants to keep carriers like AT&T sweet as they increasingly cap data plans to stop their public networks choking from smart-phone use.

The Windows Phone Music store

Applications that download music must include the Windows Phone Music store, a move designed to force music publishers to stuff Microsoft's music mart with copies of tunes also available elsewhere, making Microsoft's music store an appealing proposition to shoppers.

Finally, VoIP is allowed, unlike a year ago, while Microsoft's come over all Jobs-like and banned porn from its marketplace - a move that will help shore up Android. ®