From the official (and slickly new) Lumia WOA web site intro:
The Windows You Know and Love
This project brings the Windows 10 desktop operating system to your Lumia 950 and Lumia 950 XL. It's the same edition of Windows 10 you're used to on your traditional laptop or desktop computer, but it's the version for ARM64 (armv8a) processors. It can run ARM64, ARM and x86 applications (the later via emulation) just fine.
So yes, in theory, one might have the very latest Windows 10 builds in 2020 and beyond, all on a five year old Lumia phone, including official Microsoft x86 app support for old DOS and Windows applications. But don't get too excited, since the project still has a long way to go and even if it fulfils all its aims (by, say, end of 2021), you'd then have a still unsupported phone whose battery only lasted an hour or two on a charge. After all, the Lumia's processor, battery, and thermals were designed to run the far lighter Windows 10 Mobile. Yes, the kernels were the same, ditto much of the middleware and apps back in the day, but Windows on the Desktop has a lot more going on under the hood, plus it's written to expect a more powerful chipset backed by a huge battery or mains power.
In particular, the following limitations still apply:
- Only Lumia 950 XL and 950 are supported.
- Cameras don't work at all (the biggest shame, given the speciality of the 950 series). This is because the 950 series cameras (and indeed previous PureView cameras from Nokia) are bespoke and the Lumia WOA project has no access to the proprietary drivers or, indeed, imaging algorithms.
- Phone calls and SMS currently are either not working or have configuration issues on the latest builds (earlier builds are fine, so presumably this will get fixed soon), plus MMS has never worked.
- Non-original batteries won't work properly.
- Wifi disconnects when the phone is locked.
- Windows Hello (iris recognition) doesn't work.
- Part of the chipset is currently broken on the 950, so the device runs even slower.
You see what I mean about suitability for actual use, at least. In fairness, the number of things which the Lumia WOA team have got working is impressive:
- Wifi (2.4 and 5GHz)
- 10 finger touch and 'right click' emulation
- Bluetooth (with some caveats due to Windows bugs)
- SD card support
- All buttons working
- Battery charging
- Display brightness control
- Speakers, microphones
- Gyrometer, accelerometer, ambient light sensor
- USB Type C data, charging
As evidence of the latest possible addition to the latter list, we have photo proof from Tourniquet on Twitter:
Best way to use the HP Laptopdock: Lumia 950 XL with Windows 10 on ARM :D pic.twitter.com/0x6Wkfyd9J— Tourniquet 💻 (@wenti_man) November 18, 2020
So it seems as though HDMI out is the next hurdle to fall. Why is so much still not working? Because so much of what made a Lumia tick is proprietary Microsoft (and before that, Nokia) source code that has never been released and which only exists in the binaries in place on working Lumia 950 XL/950 in people's hands. Just taking a working ARM-compiled OS like Windows 10 and trying to stuff it into an existing handset is like putting a Ford engine into a VW car and wondering why nothing works other than the engine ticking over. There are SO many things to join up and adapt.
Of particular interest in all this and worth noting are:
1. The new Lumia WOA Project web site
It's slick and clean, with a glossy introduction, download/instructions page (if you feel brave enough to sacrifice your personal 950 XL or 950), and a status page, listing known issues and the status of each subsystem in the project for each device (including for the mysterious 'Microsoft Hapanero EB2+' test device, I wonder how many of these exist?)
2. Mobile Shell
This is important, a separate application that can be found in the Windows 10 Desktop Store, for it brings the 'Tablet' mode (designed for the Surface Go/Pro series) to the vanilla Windows 10 Desktop installed on the tiny-screened Lumias. Without this shell interaction with the UI is very fiddly indeed. It supports both portrait and landcape mode and becomes the front end to a WOA Lumia test device.
Interestingly, this installs fine on existing Surface Go/Pro (I tried), though it essentially implements the existing Tablet mode - which you could already get to from the Surface Go/Pro action centre.
Comments welcome if you're tempted to try all this (the install instructions are relatively short now) or have indeed taken the plunge.
PS. Me, I want a working 950 XL - to mis-quote the Monty Python line from 'The Meaning of Life': "My Lumia 950? No, you can't have it. I'm still USING it!" Having said that, there will a come time in 2021 when even I will take the plunge. And I'll report back then!