Microsoft plans a central market to sell programs for cell phones running the Windows Mobile system. It hews closely to the setup of Apple's App Store for iPhones, with one notable exception - Microsoft promises to communicate more openly with outside software developers.
Apple started what has become an "app store" arms race a year ago, giving software programmers a single place to market applications to enthusiastic iPhone owners.
The overnight success of the model - Apple claimed 10 million downloads in a weekend - was followed by Google's similar one-stop shop for its Android phone system.
Microsoft, Nokia and Research in Motion have announced similar intentions recently.
Redmond, Washington-based Microsoft was set to reveal more details of its own effort on Wednesday local time.
Like Apple in its App Store, Microsoft plans to take 30 per cent of sales from the Windows Marketplace for Mobile. Software programmers who want to sell applications through the Microsoft store must pay $99 a year for the privilege, the same fee Apple charges. Programmers can set their own prices, starting at 99 cents, or give their programs away, as long as they pass Microsoft's muster.
Apple's App Store gave programmers a way to profit from the iPhone's mounting buzz. It also drew criticism from some who said the company is too secretive about the process.
Developers have complained that it takes weeks or more for Apple to approve or reject their submissions and that reasons for rejections are murky or inconsistent.
Apple declined to comment.
Microsoft vows it will be more forthright and responsive than Apple has been.
Inigo Lopez, a senior product manager for Windows Marketplace for Mobile, said in an interview that Microsoft will tell software makers specifically what kinds of programs it will accept - and what won't fly. He offered few details, but said criteria will include security, content and how much of a wireless carrier's bandwidth an app eats up.
"The rules will be very objective," Lopez said.
Software makers will be able to log on to a Microsoft site to see where programs stand during the submission process and review sales figures for approved applications.
More than 20,000 programs already exist for Windows Mobile phones, and cell phone owners can seek them out on sites like Handango.com and PocketGear.com.
But the sites aren't well-publicised and there is no single place to get all of the apps, posing a distribution problem for the software makers.
"Microsoft should have done this a long time ago," said Michael Gartenberg, vice president of strategy and analysis for Los Angeles-based market research group Interpret.
Microsoft prides itself on long-standing relationships with programmers whose fresh applications keep consumers interested in buying a new Windows computer, for example.
But a smash hit on Apple's centralised repository of iPhone programs could mean big business for small developers. Gartenberg said Microsoft must get its own store up and running to keep those developers from switching to Apple.
Microsoft said developers will be able to start submitting their programs this summer. Once the store is up and running, Windows Mobile users will be able to buy programs through an application on their handsets or from a website.