Today, Microsoft Corp. announced new operational details of the Windows Marketplace for users of mobile devices where developers build and sell applications.

The firm offers 70 percent of all revenues as well as transparency throughout the certification process and a flexibility to set prices in each market for developers hoping to distribute their applications via the system.

Windows Marketplace for Mobile and Windows Mobile 6.5 enables developers to maximize revenues while having more time writing innovative applications.

“Microsoft’s decades-long relationship with developers has led to some of the most exciting innovations the industry has seen. We’ll continue our successful collaboration with developers through Windows Marketplace for Mobile, which will provide a broad reach to customers,” said Andy Lees, senior vice president of the Mobile Communications Business at Microsoft Corp.

With more than 20,000 applications are already in market, making Windows Mobile among the most popular platforms for developers, Microsoft claims.

The firm said developers can utilize familiar tools and technologies to build unique experiences for the Windows Mobile platform through Windows Marketplace for Mobile, including the Windows Mobile 6 SDK and .NET Compact Framework 3.5

Tools to begin developing applications for Windows Marketplace for Mobile are available at developer.windowsmobile.com.

“With the new Windows Marketplace for Mobile and our great development tools, Windows phones represent an incredible opportunity for developers everywhere,” Lees said

However, there is a charge of $99 as introductory annual registration fee which includes up to five app submissions and adds that it will run a rigorous certification and testing process before Windows Marketplace apps go to market. Registration is expected to open in the spring, and submissions will begin in the summer.

Further details will follow once registration opens in the spring, the firm said.