another part of the hint is "across everything"... That's why my wishful thinking could only speculate they're gonna release some version of windows phone to load in android devices and maybe they've even found a way for iphones (jailbroken or not). Of course they'd have to release a desktop program to use for this feature. Think about it, android devices can be flashed with custom roms, why not a variant of wp? "we can do that?!?"
also, msft is keen on getting people on board to use their services, that's where they expect money to flow from. Not to mention, they're practically giving away wp for free, they might as well release it "into the wild." msft is a corporation, a for profit entity, this 'surprising move' must be financially motivated for the bigwigs to approve. They already have apps for their services for ios and android. If people are interested in having full integration of these services with their os (hello cortana, onedrive, xbox), they can flash a wp rom into their device. Of course this requires msft to focus development of their services integrated with wp... Something a lot of us here have had gripes with.
Such a move would upset android and apple. Apple won't release ios out there. Android, it's out there but being open source and very customizable, at the expense of security, is too fragmented. Wp, if released properly and 'curated' by msft would be great as a unified, secure os for arm devices.... That's like taking a page from the success of windows in pcs, it can be installed in machines meeting minimum requirements. That would "upset the world across everything."
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