Microsoft confirms full Windows 10 on ARM won't be coming to existing phones

Windows Phones
Windows Phones (Image credit: Windows Central)

Ever since Microsoft announced that full Windows 10 would be coming to ARM, many Windows phone fans have assumed this means phones like the Lumia 950 and Lumia 950 XL will be getting an update to full Windows 10. File this one under "totally obvious," but today Microsoft's Joe Belfiore confirmed that existing Windows phones won't be getting full Windows 10 on ARM.

Joe Belfiore provided a rather technical and insightful explanation as to why existing phones won't be able to run full Windows 10 on ARM during the Windows Insider Mixer Broadcast (47:20 minute mark) :

The Windows 10 on ARM effort is about enabling the PC experience on devices that are built on ARM so that they're connected all the time and have great battery life. So the experience is a desktop PC experience, it's not a phone-like experience. For phone-like experiences on ARM, we have Windows 10 Mobile. What Windows 10 on ARM is, is a desktop-like experience so that you get the battery life that ARM processors tend to have.The other thing that's interesting about this is that in all cases where you build ARM software, it's not so easy to just put it on another device. The OS intermingles with what's called the BSP (board support package), and that's how the software talks to the SoC. There's special work that has to be done to get the OS talking to the BSP, talking to the SoC, so it's not like the PC ecosystem where we write an OS in the same binaries that run on lots of different PCs. With ARM devices with SoC, you have to more closely target it. So that is often the case why it's more challenging for us to get updates to a wide range of ARM devices. They're all quite different, which adds delay, and as the number of people using those devices gets smaller, it unfortunately makes less sense for us to invest more time and energy in that.

In short, Belfiore explains that the full Windows 10 on ARM effort is about enabling great battery life and sleep on ARM based laptops and tablets, and not about bringing full Windows 10 to phones. Now of course, this doesn't mean Microsoft isn't working on something for phones. Rumor has it, Microsoft is planning yet another attempt at Windows phone, that may show up as early as next year.

We believe that this next attempt at phones won't be launching for existing handsets however, which means devices like the Lumia 950 will be keeping with Windows 10 Mobile. We do know that CShell will play a big roll part in it, but outside of that not much else is known about the project.

Full Windows 10 on ARM will be launching on tablets and laptops with Snapdragon 835 processors later this year. In the meantime, are you interested in buying a device with Windows 10 powered by an ARM processor?

Zac Bowden
Senior Editor

Zac Bowden is a Senior Editor at Windows Central. Bringing you exclusive coverage into the world of Windows 10 on PCs, tablets, phones, and more. Also an avid collector of rare Microsoft prototype devices! Keep in touch on Twitter: @zacbowden.

478 Comments
  • Jesus Christ.....again?
  • Well that was totally expected. No current phone would be able to run full Windows 10, even Elite X3. We're all now waiting for something aka Surface Phone.
  • They demonstrated Windows on ARM on the exact same specs as the Elite X3. Belfiore excuse is B.S.
  • They also said that it was ONLY for devices with a SD835 and NOT SD820. I'm not sure why that part is always left out in these discussions, it's literally the most important fact that we DO know about Windows 10 on ARM.
  • They did not say that at WinHec last year. The guy from ARM literally held up an Elite x3 and said the demo was running on the same hardware. I don't care so much that they don't bring WoA to SD820 devices, but the plan to branch off Windows Mobile OS from Windows PCs running ARM is no different from what MS did with Windows RT and Windows Phone in 2012. This plan is awful, more awful than not supporting Elite X3 and Alcatel Idol owners. Microsoft is an embarrassment, they are admitting technical incompetence here.
  • Yes they did it as a DEMO. That doesn't equate to them saying it'll be available on Elite X3 and other newer phones. Technically, maybe they can make it do that, but maybe it doen't run well like how windows 10 on really cheap tablets with less than optimal hardware can suck even though it technically works. 
  • Look buddy don't get there and think you're speaking to a room full of out the womb babies. From the moment you demo something running and with the speed that the vid showed it functioning at didn't suggest they played it at 2X the normal speed. It clearly showed it works. You build up expectations and then to say sorry you're going to have to wait another 2 yrs or so and spend obviously wayyy more than what you bought the 950,X3 or the Idol 4S for.
  • I could not agree more with your statement. Microsoft needs to smarten up no doubt.
  • More a proof of concept, and a direction hint. I didn't expect it on the 820 devices.
  • Save your breath dude, Microsoft can do no wrong in these guys eyes.
  • WoA is RT done right.
  • Except for the fact that it is nothing like RT.
  • Except for the fact that it is nothing like RT.
  • Except for the fact that it is nothing like RT.
  • Except for the fact that it is nothing like RT.
  • Can we please get this issue resolved already?
  • No one with half brain not expected full Windows 10 on ARM for existing phones, because there are no phones with SD835 soc. But that does not mean there will be no update for the Elite X3. CShell is next thing for mobile, and we already saw that bild in action. Perhaps you should try to explain better to some what CShell means, as some apparently do not get it... With CShell they could bring anything from desktop to mobile. Even win32 apps. If oem decides to do it. Ofcourse they need to bring appropriate hardware for it.
  • I dont think that's what cshell is.
  • CShell is same OS, only scaled differently for different screen sizes. With the appropriate UI for those screens.
  • C-Shell - Composable Shell - is just the UI part. C-Shell doesn't bring anything and everything from Phone to Tablet to Desktop, doesn't let popular Desktop Apps run on Phones  
  • I don't care about full Windows 10 on ARM.  I want cshell and an improved continuum experience.  That's all I care about.  Lumia 950XL should be able to run cshell.   They just don't seem to talk about it much.
  • They demoed Windows on ARM on the 820 because the 835 wasn't on the market yet. What don't you understand about this?
  • So Dan if I may ask, what little hope can we expect for our L950s? Not even the slightest changes in CShell or Continuum?. Something to make our current devices better for work and usage till our next big phone. Any hint to give me some hope?
  • I will be happy if Microsoft gives us a ARMv8 version of Windows 10 Mobile and it continues to run UWP apps.
  • I have a 950, and even I can ask "who cares what happens to it?"
    ..........
    Waiting on the next generation of Windows on Mobile from MS.
  • Yeah I honestly don't want full Windows 10 on ARM on my l950. I would like a better continuum, but I'll just wait for better hardware when it does come out in a few years.
  • Yeah. And, we're going to have to wait... Our current devices aren't gonna last forever, so It's gonna be "ok" hardware with a nasty looking OS, or terrific hardware with a boring looking OS. Take your pick for now.... All I know is that a potential Surface Phone could give us back what we had with Lumia devices.. Beautiful hardware, with a beautiful OS.... Until then I have to find the most exclusive Android device to hold me over😣😣😣
    Can't believe I just said that. Lol
  • I am stopped hoping from Microsoft their mobile first cloud first theory.
  • I have a 640 and have been feeling like the fifth wheel until now. Now I feel like the old spare in the trunk with a flat.
  • I got my 640 for $50 a few years ago on a Christmas sale. It's a decent phone for what it is but you do know it would freeze up if it ever tried to emulate a desktop OS. Start saving your money for a new phone.
  • I agree, but when I need desktop power, I use a desktop, or at least a laptop with a decent size display. Do I really need that much power on a six inch screen? The current suite of Office apps on mobile is quite good, just missing a little of the functionality I enjoy on the desktop. The new incarnation of "mobile" would need to be a game changer for me to spend the cost of an iPhone when so much was made available for the cost of one month of service.
  • You are right when it comes to MS the only things you can do is either stop buying from them or accept that you, as a customer, count less than zero to them. You are in this second category, happy to be f* from behind each time and asking for more :-D
  • I see no evidence that anything substantial will happen with 950. I mean, UWP exists and those phones will continue to run UWP, but the OS won't be advanced outside of bug fixes and stability. Honestly, no one has a clear idea what MS's mobile plans are these days.
  • But they do have a mobile plan.
  • allegedly.
  • "But they do have a mobile plan." allegedly.
  • Only Jason Ward has a mobile plan for them and sells it as their plan
  • Sure they do.  Nadella's plan for mobile is to simply let it die.  He won't kill it per say, but he will let it wither and slowly, painfully die -- taking those of us believers that are still on the product.  It isn't cloud first, so he has no real interest.  If I had to guess, he probably sees this as one of Steve's follies and doesn't really want to continue to deal with it.  That has been pretty obvious ever since he took over.  Despite having a superior product, all we get is that he talks a good game, says what he thinks people want to hear, and has NEVER backed it up with actions.  The only hope that mobile has at Microsoft is a change at the very top.
  • The reality is that those devices are old.. Even if WM was a thing, and had 20% market share, we can't expect for MS to support them forever... Who in the world would expect MS to support a 3 year old device with future software that's yet to be released?
  • wow rodneyej, pragmatic and realistic! I fear your levelheadedness is frightening some of the keyboard warriors here.
  • I see this statement as truth. All things must pass. Nothing lasts forever.
  • True, but it's not like they have any new devices. It shouldn't be difficult for them to keep supporting the hardware that is out there since that's all there is. It's not like android with thousands of different phone models.
  • Well, they will support it, just not with their newest technology.
  • Most of all MS
  • My biggest issue with MS's current "feature2" strategy is not that it won't receive new features, or cshell or continuum updates, but that W10M loses compatibility in terms of new API's that are part of RS3. It essentially breaks "one core" & "one Windows". As such, MS simply cannot release feature2 as if it were RS3 for mobile, because in terms of API's it will not be in sync with big Windows. Even RS2 did not contain anything relevant for mobile, but at least we got all the fluent design stuff. And wasn't that always the advantage of "one Windows"? MS didn't need to do any special for mobile: it would simply get it all "for free" from development done for regular Windows. This is why I don't "get" this feature2 stuff. It makes things more complicated by creating multiple Windows versions. And this in a time where there's supposed to be more and more convergeance between the different editions.  
  • "So the experience (WoA) is a desktop PC experience, it's not a phone-like experience. For phone-like experiences on ARM, we have Windows 10 Mobile"
    What is that supposed to mean?. The we've w10m sound weird knowing all of us the bad condition the whole system is. No phones, no services, no good solutions to issues, no nothing.
  • that's a much better question. what did he mean by that? so far everybody assumed (key word) MS would merge w10m and w10 going forward. is he talking current status? are they still working on bringing w10m up to par with w10 (they did mention that a few months ago) and will it be a special version just like w10 iot? Whatever they have up their sleves it better be that good to justify this secrecy that has brough so much ill will to MS from its windows phone fans  
  • Whatever the strategy turns out to be it requires something Microsoft has been unwilling/unable to do with mobile....Back it 100% with full commitment that everyone can see, that means throwing money, BIG money at marketing, branding, opening stores globally and taking the fight to where the fight is rather than standing around the ring watching, waiting and acting half heartedly.
  • You mean the 2 year old discontinued phone isn't going to be getting a massive new update....? I don't understand the commenters here obsessing over their 2,3,4 year old phones not being completely remade into new devices.
  • Stability my butt. :( They have made the bluetooth stack nearly useless which seems to be almost intentional. They could have at least left that alone in a working state.
  • Windows phones currently will still receive feature2 builds and maybe a last Creators Update but that is about it.
    .
    Now MSFT will expect any one going forward to buy a new device.
  • Exactly, because the newer chips gives it some headroom for updates something the older chips just not going to swallow. ARMs processors move up the power threshold gives Microsoft something to work with and starting with this upcoming Snapdragon which Samsung is presently using going forth it's all about being capable of receiving updates which will become the market driver for more powerful devices.
  • Going forward people are buying new devices... Apple and android.
  • The nokia 8 seems to have good specs
  • @robert1312: And not much else.
  • No problem.  Everybody is free to choose.  Microsoft is not forcing you to buy their phones if you don't like it.  The truth is people have to wake up.  Windows phone/mobile failed because they made the damn thing run smoothly on low end devices and low end devices do not generate money. Low end devices do not generate enthusiam and aspiration, people buy phones because of specs.  Android is slow as a snail on low end hardware that's why they push people to high end specs, that is their strategy. 
  • The same hope that every phone has when it's left for dead...i.e.  1020 when w10m was released...NONE!  
  • Woooo hoooo fanboy tears truth downvotes!
  • If the new mobile device to be released in 2018, it will probably use SD845 which would use 7nm process chip.  Besides the performane boost, it focuses on supporting MR.  LG G7 will use that procssor.
  • what's MR?  
  • Mixed Reality (includes AR, VR, and ER)
  • It would help immensely if Microsoft stopped showing off the hardware we have in our hands today running software they plan to release later, and then as the release date nears saying nope. Spend a few thousand on a modelless prototype device to demo on, and spare the PR nightmare that just pisses off the customers.
  • I agree because why show us it running on X3, or why have another vid showing it running on a 950, then for the clowns at MS to come out and say it's not for this or that. What I would love is for them to just shutdown this mobile crap and let us bite the bullet and move on from their crap. These same editors and MS execs don't even use their own phones. Use all the rivals' devices and then spit on us with all the vomit they tell us. The very same editors of this website say they own a 950 series, X3 or Idol 4S but do they use them only? NOOOO they don't it's just to say they update them and use another as daily driver. You honestly think that if the same Nadella used a 950 only that it would be in its current state?
  • The average consumer doesn't see, or care about this.. MS doesn't have time to care about what 1/100th of 1% of what some fans see at Build.
  • The average consumer won't buy a Windows/Surface Phone. They don't care what ARM is. All they care for is a good camera, the newest apps and a trusted brand.
  • Isn't that an average "iPhone" customer?
  • So how.......does that help the idea of a MS branded smartphone if they make one.
  • No, but then the average consumer isn't writing articles or commenting on them either. But these are the people the average consumer will get advice from.
  • Developers prototype things on existing hardware because they have to; the real hardware often doesn't exist yet. As the real hardware becomes more available, they add features to the software that won't work on the prototype hardware. The "alpha" version of the Xbox 360 was a PowerPC Mac with an ATI graphics card. By your logic, that means that Microsoft should have made all Xbox 360 games run on Mac.
  • These days, no matter what the platform, there is absolutely no reason to run the demo on branded hardware. Microsoft has, on multiple occasions, done exactly this. And of course, as new features are added the software no longer works on prototype hardware. More reason to strip the branding and NOT hold up a [insert model] and declare, "Look, we are running this on a [model] today!" You would think they would learn by now that people take that to mean the new software will run on a phone of [model]'s capability. BTW, your PowerMac-Xbox analogy falls flat, because it was obvious the plan was to build a console--a totally different platform altogether.
  • Quit using historical facts as proof of an argument Daniel. You should know by now that has no place in our current world. =P
  • Was that Dan or noirsoft?
  • Which, as was pointed out, means none of the current phones will run it. Fine by me. Something new would be nice.  Still waiting for that nice 8" LTE connected WIn10 tablet with pen & onenote.  (any of the atom-based ones have iffy battery life and performance is ... iffy.)  
  • If the market share of Windows phones had increased when the Lumia 950, 950XL, HP Elite x3, and Alcatel IDOL 4 Pro were released then MSFT would have more reason to support it.
    .
    Today Windows phones account for less than 1% market share so it's pointless to spend any resources on existing devices
  • I think that they could have grown to double digits with the 640 line outside of the US if they would have kept the Nokia developers to expand the Lumia apps.
  • They could have also included radios supporting all frequencies. The added cost would have been minimal and allowed Microsoft to differentiate itself by advertising the devices as "ready when your carrier is." Advertising to compensate for a weakness under your control is always going to have a huge price tag, and not just monetarily.
  • by the latest data, 0.1% to be more precise.
  • That's not a fair assessment. NONE of those phones work on Verizon.
  • How is his excuse B.S.? Belfiore clearly states that they can support some of the existing hardware, but they chose not to because developing for different chipsets needs more resources, adds more delay, he did not say they can't do that. Windows Phone and Windows Mobile, if you see from the start, has always supported only specific chipsets: L920/820/925/928/1020 had the same chipset, L720/620/520 had the same chipset. Next Gen, L1520/930/Icon shared the same chipset, L830/730/630/638/640/640XL had the same chipset, L430/530/540 had the same chipset - only the 950 series and L650 and L550 broke that trend. They always stuck to a certain chipset for which the OS was made compatible, and hence we did not see refreshes or model variants. A L830 should have arguably had a 600 series chipset, but they chose a 400 series instead because that's what most of their handsets had. Even the 640 that came after did not get an upgraded chipset. It was always a bit apparent to me that Microsoft's OS development might be a limitation. While I am not pleased with the response, I wouldn't call it B.S. - it's like saying the L920 and L820 or even L620 can run Windows 10 Mobile - but doesn't mean it's a good experi