Microsoft Mobile App store sets the parameters for what app developers cannot submit for consideration.
Windows Marketplace for Mobile is the application store that is being launched by Microsoft for mobile phone devices.
Like Blackberry and Apple, the company is encouraging third party applications, however it has put the kibosh on certain things and there is no doubt where they stand on certain issues.
One is VoIP (Voice over Intenet protocol). Any app that tries to get around the network operator is a no-no, according to Microsoft. Also on the list is anything that will muck up the integral default applications of your phone. Files that are bigger than 10MB will not be able to be emailed via your mobile, as well as any function that tries to get users to pay for an upgrade an application outside of Windows Marketplace for Mobile.
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to their website.