Up until now, Microsoft has taken a rather laissez faire attitude toward application development -- anyone with a copy of Visual Studio and half an ounce of coding know-how could whip up and share whatever little programs they want. That won't be the case inside Windows Marketplace for Mobile, Microsoft's answer to the App Store, and the company is now listing a number of guidelines that devs must follow for the fruits of their labor to be included. Top on the prohibited list? Apps that themselves sell other apps. Second rule of the Marketplace? No apps that link to apps that sell other apps. Also banned is VoIP over cellular networks, apps that run non-managed code (i.e. don't stay inside the sandbox MS has set up), anything that distributes a user's information, and downloads that are bigger than 10MB. Not mentioned? Anything to do with naughty content, meaning purveyors of explicit executables might not have to make concessions. Full list of 12 commandments after the break.
Update: In case you didn't figure it out for yourself, Arnoud from Tweakers.net wrote in with confirmation that the no-VOIP rule is in place at the request of the providers.
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