Are we supposed to think about Windows RT as a different product from Windows 8? That's the question we put to Windows 8 marketing head Tami Reller in a briefing with TechRadar recently.
"In a way you are," she says, "it definitely has a tremendous amount in common – a tremendous amount - with Windows 8 but yet it is its own experience.
But we wanted to know the answer to the key question surrounding Windows RT - the OS on new ARM-based Windows tablets such as Microsoft Surface, Asus Vivo Tab RT and the Samsung Ativ Tab: how will consumers know that it's different than Windows 8? "We definitely are working hard at retail or at any point of purchase to make sure customers do understand what Windows RT is.
"And while, from a Start Screen perspective and a Windows Store perspective, it has exactly the same capabilities and appearance - in the desktop it is different. We say it works exclusively with apps from the Windows Store, it does come with Office and it does not provide desktop compatibility.
"We're trying to be very [frank] about describing that. It's a change. It's not compatible with desktop software so we want to make sure we say that in very plain terms and that we describe that more on Windows.com and in any other retail or other point of sale."
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Problem for partners?
Windows RT poses a challenge for hardware developers, but not for software developers according to Windows 8 program manager Gabriel Aul.
"The apps that are Windows Store apps, they don't have to explain anything. They just build the app and it runs on everything. A developer might write a desktop app and a Windows 8 app – they might already do that, they have to explain what's different about the two.
But Aul dismisses suggestions that desktop development will cease – and also that people will be confused by the distinction between the two environments. "We're already seeing developers continue to build desktop apps – Photoshop for example, it's heavyweight, it uses windowing. That's not something we're going to see as a fully Windows 8-style app in the short term.
"But other developers are choosing to move and focus fundamentally on Windows 8 style apps. It goes back to OEMs and retailers; the purchase is where the distinction needs to be made, after that it should work as they expect."
"[We need to] make sure that packaging and descriptions and training do the trick."
Outlook on RT
There's no Outlook available for Windows RT ("unless you're using Remote Desktop! That works very well!") and we were keen to find out Reller's take on where this would leave business-orientated RT tablets like the Dell XPS 10.
"I think it depends on the business. When you look at Windows RT and business interest in Windows RT devices, we're seeing a lot more interest from businesses that have a vertical focus and a lot of mobility.
"So the case if I have an employee roaming all day and they're going to be using one app or one workstream of apps where they're sort of intensely focused on those things – RT will be good for them. For Outlook and other desktop scenarios you'll need Windows 8 Pro.
Microsoft has been keen to stress that one of the benefits of Windows RT may be in terms of performance; installing apps shouldn't slow the system down. "The upside of not having desktop compatibility is that you don't have any apps that impact negatively on the performance of the system, so you do have this quality over time and a system that's nicely predictable." In other words, everything can be controlled by Microsoft as it wil audit the apps.
"What has been very helpful is that we've had a couple of summits for corporate users on campus with our engineering team," adds Reller. "Most of them have completed or are in the midst of their Windows 7 migration from largely XP so they believe they'll exist in this environment where they've XP, Windows 7 desktops and some Windows 8 departments.
"Windows 8 will work seamlessly with Windows 7 and then with Windows RT so you can have a common set of applications. Then there's Windows to Go [the portable corporate version of Windows 8] and so you've got your USB stick and you're just moving [your PC] between machines. It's among the top reasons why CIOs are interested in Windows 8. It does feel like magic."