Microsoft mum on Office suite for Apple iPad

Microsoft does offer native iOS versions of some Office applications, including its OneNote note-sharing software, Lync communication suite and SharePoint collaboration site, as well as its SkyDrive online storage service.

But the more than 100 million iPad owners, many of whom want to bring their devices to work, have to use the limited online versions of desktop staples Word, Excel and PowerPoint.

Morgan Stanley analyst Adam Holt estimated earlier this month that Microsoft could generate $2.5 billion in extra annual revenue from Office on iPad by next year, less the commission Apple would take on sales of Office through its App Store.

But the risk for Microsoft is that putting Office on the iPad takes away one of the key advantages of its own Surface and other Windows tablets, that already run Office natively.

Removing incentives to buy Windows tablets would be a blow to Microsoft's flagship Windows unit, which although less profitable than Office, is still key to the company's overall strategy.

Asked by one investor at the conference when he would be able to use Excel on his iPad, DelBene instead pointed the questioner toward Microsoft's own Surface RT and Surface Pro tablets and urged him to use Web-based versions of Office apps.