Application compatibility

With a few exceptions, existing Windows applications will not work on RT. That is partly because ARM processors have not supported major desktop Windows client OSes in the past. But existing applications will work on Windows 8, as previous Windows OSes over the past few decades were written primarily for Intel or Advanced Micro Devices processors. Microsoft is adopting a new application model with Windows RT and 8, and users will be able to download applications through Microsoft's application store, which will show up as a tile in the user interface. "I think that Windows' new app store is ... a move from Microsoft to catch up with the changing distribution channels for software," said Nathalie Lussier, a technology consultant in Brooklyn, New York, who is looking into Windows hardware.

Peripherals and accessory compatibility with Windows RT

A lack of drivers may prevent some older peripherals such as printers or cameras from working with RT. Some device drivers may not have been written to work with RT -- an issue that's similar to existing Windows applications not working with RT. It may be worth checking with device makers to see whether they have drivers for RT. and have published lists of printers that will and won't work with RT.

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