It appears a Microsoft promise to officially facilitate homebrew development on the Windows Phone 7 platform doesn't extend to emulator apps, with one developer reportedly told his NES emulator will not be allowed in the Marketplace.
According to WMPoweruser.com, hobby developer Matt Bettcher ported code from the My Nes and SharpNES projects to Microsoft's mobile platform to create the NES EMU 7 project. Mr Bettcher claimed he contacted Microsoft and was told his work will not be allowed to pass through the gates of the Windows Phone Marketplace. Not content with that answer, he is now asking for community support to pressure Microsoft into changing their mind.
''Microsoft is telling me I can't make an NES emulator! I can't invest time into this for nothing. If I can't get this resolved by MS then I will create a Codeplex project of what I have done so far and let the developers decide!'' he wrote on the page of a YouTube video demonstrating the emulator.
In the same posting, he claimed the emulator runs at about 10-20 frames per second on a Samsung Focus and said he aimed to have the project running full speed with sound.
For its part, Microsoft gives a strong indication as to its stance on game emulation on Windows Phone devices. In a post on the official App Hub forums (also quoted on Mr Bettcher's YouTube page), it is stated that:
''Microsoft takes intellectual property rights very seriously. If you post a game/image/source that uses unauthorized intellectual property, we will delete it immediately. This includes technologies that are clearly intended to enable unauthorized use of intellectual property, such as game console emulators.''
As WMPoweruser.com pointed out, even notoriously over-cautious Apple have allowed emulators in their App Store, albeit after a fair amount of controversy - and a NES app is not among them.