VoIP applications are one of 12 application types that will be verboten at Microsoft's Windows MarketPlace for Mobile store when it launches in the second half of this year. Microsoft also doesn't like apps that change the default browser on a device.

Microsoft is winning praise for posting a clear set of rules as to what can and can't go up in its applications store, but is likely to get criticism by open networks/network neutrality types who will ask why. Third-party VoIP services that run over an operator's data network, thereby bypassing the billable voice minutes bucket, aren't the sort of thing that service providers really want to see available.

PC World speculates that the ban is limited to "VoIP services" and "presumably" developers will be able to offer VoIP apps using Wi-Fi, but there's no way of truly knowing until we see the apps out there. Developers are also being forbidden to offer up programs that change the default phone dialer, SMS or MMS service interfaces.

For more:
- PC World details Microsoft's Marketplace for Mobile store. Post [1].

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