It will be interesting to see how Microsoft reacts to the double dipping of these OEMs. While a PC with Windows 8.1 still means Microsoft has been paid for the operating system's license, the company will not be happy with PC Plus and its implications.
"This should scare the heck out of Microsoft," said Moorhead. "They should be very, very afraid because if goes widespread, it demotivates developers to create native Windows apps."
As evidenced by the size of the Windows Store's app stock and the rushed quality of some apps, including many from top brands, Microsoft already has a hard time convincing developers to invest in a platform that has yet to gain a significant portion of the OS market. In addition, it's a platform in which many users seem comfortable sticking with the traditional desktop half and its familiar mouse-and-keyboard applications.
"Google does not actually sanction this and Microsoft has not taken a position on this dual-OS integration idea yet," said Bajarin. "It will be interesting to see if this takes off and, if so, how Google and Microsoft will feel about it once it hits the market."
If Microsoft isn't able to convince OEMs to drop the PC Plus idea, Moorhead said, it has carrots and sticks for more serious arm-twisting.
How Microsoft could respond
"I think what Microsoft will do is pull co-marketing funds from any SKU that offers Android," said Moorhead, referring to "stock-keeping units," or each individual PC model that hews to PC Plus. That would effectively raise the OEMs' cost of doing business for those PCs that support Android apps.
And if, as Bajarin said, Intel is behind PC Plus, then Microsoft faces another defection from the partnership that brought in billions for each company over the last two decades. Intel already makes processors able to run Android, and if its support for PC Plus relies on customized silicon it offers OEMs, the backing will further fragment the Wintel oligarchy.
Microsoft declined to comment on PC Plus and OEM plans.
Neither Bajarin or Moorhead had seen PC Plus in action, and Moorhead refused to offer an opinion on its chances until he did.
"I have to see the experience before I can weigh in," said Moorhead. "It could be completely transparent [the switch from Windows to Android and back], or it could really screw up the experience. There are a lot of ways you can confuse customers, and this has the potential to confuse people who use it."
The jarring discontinuity of Windows 8.1 — which boasts not only a traditional desktop but also the tile-based, touch-enabled Metro user interface (UI) — could be trivial compared to a disastrous combination of Android and Windows UIs.
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