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Microsoft announced in March that Windows 10 was now installed on more than 800 million active devices, up from 700 million in September.

But, according to documents seen by Microsoft watcher Paul Thurrott, the official and more precise figure that Microsoft circulates internally is that Windows 10 is now on 825 million active devices – a total that's still well shy of the one-billion target it once predicted for mid-2018, due partly to the failure of Windows Phone.

Perhaps more importantly, the documents also shed light on how Windows 10 fits into the company's slow-burning cross-device push with iOS and Android mobile apps for Windows 10, and who's leading this effort under CEO Satya Nadella.

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Microsoft has not announced Windows executive leadership changes since former Windows boss Terry Myerson left the company last October. That was announced as part of a reorganization of the Windows and Devices Group (WDG), one of the key teams alongside Office, Cloud and Enterprise, AI + Research, and Gaming.

Now Microsoft has promoted Eran Megiddo to corporate vice president of Windows and Education. Megiddo has run Education, OneNote, and Wunderlist for the past couple of years and as of last April reported to Microsoft corporate vice president Joe Belfiore.

Belfiore once headed up Microsoft's Windows Phone teams but these days leads the Windows client experiences team and reports to executive vice president Rajesh Jha, the head of the Experiences & Devices engineering unit.

Megiddo still reports to Belfiore under the new Windows-related role but will now focus on "Windows client direction and strategy", according to Thurrott.

Additionally, Belfiore is now the head of Microsoft's Essential Products team, which Microsoft refers to internally as 'EPIC'.

EPIC is part of Microsoft 365 and the group leads Windows 10 apps, Microsoft Edge, OneNote, and Android and iOS mobile experiences, including Microsoft Launcher, Microsoft Edge, OneNote, To-Do (Wunderlist), Microsoft News, and more.

Belfiore lists his current role on LinkedIn as corporate vice president of EPIC, a role that's focused on user experience for essential products.

He says he leads the team "that builds the user experience for Windows 10 and many of Microsoft's other 'Essential Experiences' like Microsoft Edge, Microsoft News, OneNote, Education products, and a range of mobile products including Microsoft Launcher, Edge, and others".

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Meanwhile, Megiddo will be focused on providing clarity to Microsoft's Windows strategy, enhancing the mobile-to-Windows experience, and pushing Windows in the education market.

EPIC partly measures its success by the number of times the group's apps have been downloaded. While the Google Play Store says Microsoft Edge for Android has been installed more than five million times, Microsoft says the mobile version of Edge has been downloaded just 4.5 million times. The Microsoft Launcher has over four million monthly active users and SwiftKey 159 million.

Additionally, as per MSPoweruser, a Microsoft exec has boasted that Office 365 now has more than 214 million subscribers who pay $99 a year. To put that in perspective, the exec tells customers that Office "has more subscribers than Spotify and Amazon Prime combined".

Of course, most of these Office 365 subscriptions are from business, as opposed to consumers choosing to spend their money on music and content. As Microsoft disclosed a few weeks ago, consumer Office 365 subscriptions are less than 35 million. Spotify and Amazon Prime each have about 100 million subscribers.

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