This update had a purpose that Microsoft’s mobile and desktop systems should get absolutely aligned.
Windows 10 Mobile build 102586.29 was distributed to members of the Windows Insider program late last week and opened up to Insiders using the 950 and 950XL.
The Windows Insider program, and before it, the Developer Preview program have for a few years now enabled Microsoft to push out new builds of Windows Phone 8.1 and Windows 10 Mobile to any Windows device, even if it’s carrier-branded and carrier-locked.
Microsoft has been pushing to have Windows everywhere for years. Last year, CEO Satya Nadella again said that “one single converged operating system”. This plan, “One Windows,” has long been the goal, but getting there was complex, not least because the version of Windows used on the desktop (Windows NT) was larger and more complex than the one initially used on smartphones (Windows CE). Windows Phone 8.1 did tremendous work in bringing NT to the phone, but it was still in important ways a different operating system to Windows 8 on the desktop; while applications could share code, and many APIs were common to both platforms, their functionality nonetheless diverged, and maintenance and updating of the two operating systems was completely separate.
That’s no longer the case. It’s true that there are still some things that the phone operating system can do that the desktop can’t, and vice versa—the phone can run existing Windows Phone 8.1 applications but can’t run Win32 desktop apps, while the desktop operating system ships with full Win32 desktop support but can’t run Windows Phone software—but the core elements are common between the two variants. They’re updated together, released together, and have a large software platform, the Universal Windows Platform, in common between the two.