Microsoft

To make Windows 8 a success on tablets, Microsoft may well need help from the one company least likely to give it: Apple.

As Microsoft prepares Windows 8 for a launch that analysts expect later this year, it's busily encouraging developers to create applications that work with its new touch-friendly, tile-based Metro interface. That's important, because the thinnest, lightest Windows 8 tablets will be running a Metro-only version of the operating system specifically created for ARM system-on-a-chip devices. Without popular apps, Microsoft's tablet partners will have a much harder time selling their devices.

Apple's iTunes is clearly one of those key applications. There are plenty of Windows users who stash their entire music and video libraries in iTunes. And listening to music and watching videos on a tablet is clearly among the important ways people use the devices. If Apple chooses to not make a Metro version of iTunes, consumers have one less reason to buy a Windows 8 on ARM tablet.

"The incentive is for Apple not to do this," said Rick Sherlund, an analyst with Nomura Securities. "If I can't get iTunes on [a Windows 8 on ARM tablet], that's a big deal for me."

Microsoft declined to comment on the matter, and Apple didn't respond to a request for comment. There's little doubt, though, that Microsoft has thought about the challenge.

"We'd welcome Metro-style applications from Apple in the iTunes case," Microsoft Chief Executive Steve Ballmer said during the company's financial analyst day last September. "I don't know what we'd see there. But we'd certainly welcome those."

Windows 8 does include a way for users to move their music and video files, including content purchased without digital-rights protection, to a music app. But it's not iTunes. And, for those that aren't tech savvy, it may not be apparent how to do it.

And history shows that the availability of iTunes isn't a make-or-break proposition. The market for Android phones has thrived without iTunes. Android tablets, aside from Amazon's Kindle Fire, haven't seen much success, though that has little to do with the lack of iTunes.

What's more, plenty of other table-stakes apps will be available for the Metro interface. Microsoft will have Internet Explorer teed up. And it seems likely that other popular Microsoft apps such as Skype will be Metro-ready. What's more, both Google's Chrome and Mozilla's Firefox are both working on Metro-ized versions of their browsers.

But it's also becoming clear that, as Microsoft moves closer to launching Windows 8, users will have two different experiences with the operating system. Those that buy PCs and tablets running the traditional x86 architecture with chips from Intel and AMD will be able to run all the apps they currently do, including iTunes. But users who opt for tablets that use the ARM architecture won't be able to use all the apps they've come to expect on Windows PCs.

"This is Microsoft fragmenting itself," Gartner analyst Michael Gartenberg said.

Without the same apps available on all devices, Microsoft runs the risk of confusing consumers. And Apple is likely to be more than happy to muddle that marketing message and not deliver a Metro-version of iTunes. After all, the company has no desire to help Microsoft make any inroads into its tablet dominance.

"People are lining up in the cold and rain to buy the new iPad," Gartenberg said. "Is anyone going to line up to buy Windows 8 on ARM?"