April 10, 2015 10:05 am

New Windows 10 Technical Preview build now available for phones

By / Corporate Vice President, Engineering Systems Team

Update 4/14: We are seeing some reports of failures on Lumia 520 devices when trying to roll back to Windows Phone 8.1 using the Windows Phone Reset Tool. We are pausing build availability for these devices temporarily while we investigate the issue and work with customers who have reported problems.

Hi everyone,

As I mentioned a little over a week ago, we recently brought the partition stitching feature up to our main branch and have been testing it extensively within Microsoft. I’m VERY HAPPY to be able to get a build out to you today that has this and allows Windows 10 to be used across a larger set of phones. This is definitely not the final list of devices, and we’re still hard at work to let people with other phones get hands-on with Windows 10 in the near future, including non-Lumia devices as well.

Today we are releasing Build 10051 of the Windows 10 Technical Preview for phones to the Fast ring. This build not only supports more phones, but also has tons of exciting new features that you’ll be able to try for the first time.

Devices supported with this build

So, let’s start with the good news: a TON more devices are supported for this build, and we’re excited for Insiders with these devices to start using Windows 10 and sending us feedback.

  • Lumia 1020
  • Lumia 1320
  • Lumia 1520
  • Lumia 530
  • Lumia 530 Dual Sim
  • Lumia 535
  • Lumia 620
  • Lumia 625
  • Lumia 630
  • Lumia 630 Dual Sim
  • Lumia 635
  • Lumia 636
  • Lumia 638
  • Lumia 720
  • Lumia 730
  • Lumia 730 Dual SIM
  • Lumia 735
  • Lumia 810
  • Lumia 820
  • Lumia 822
  • Lumia 830
  • Lumia 920
  • Lumia 925
  • Lumia 928
  • Microsoft Lumia 430
  • Microsoft Lumia 435
  • Microsoft Lumia 435 Dual SIM
  • Microsoft Lumia 435 Dual SIM DTV
  • Microsoft Lumia 532
  • Microsoft Lumia 532 Dual SIM
  • Microsoft Lumia 640 Dual SIM
  • Microsoft Lumia 535 Dual SIM

* Microsoft Lumia 640’s on some mobile carriers not supported at this time.

And now a bit of bad news: In my last post, I shared a preliminary list of phones we expected to support with this flight. You’ll see that the list has remained largely unchanged with one exception – the Lumia Icon. Unfortunately there is an issue with scaling on certain devices (930, Icon, and 640XL) which makes the UI too small to be usable, and we need to add code to support new scaling thresholds for these devices. That work is underway, so we expect to see support for them in the near future. I know some of you will be disappointed, but trust me that you want us to make that fix before we send it out to you.

Getting started

Instructions on how to join the Windows Insider Program and get your phone set up are available on the Windows Insider website. Be sure to read the instructions very carefully so you can upgrade easily and comfortably.

If your phone is already on the Windows 10 Technical Preview, all you need to do is go to Settings apps > Update & recovery > Phone update > and check for updates. We’re pushing out this build only to the Fast ring today. If you’d like to change from the Fast ring to the Slow ring, just go into the Windows Insider app on your phone and login with your MSA and change rings.

Here is what’s new

Project Spartan: An early version of Project Spartan is available in this flight. It uses our new rendering engine to give greater interoperability with the modern mobile web, and includes early versions of Reading View and Reading List. For now, Project Spartan is not the default browser, and exists side-by-side with IE11. You can find it in the All Apps list and pin it to your Start Screen from there. Please send feedback on sites and design. For more details on Project Spartan on the phone – see this blog post. Be sure to also check out this blog post from Joe.

New mail and calendar apps: Outlook Mail and Outlook Calendar are the new built-in mail and calendar universal apps for Windows 10. These new apps bring a fresh UI, with a toggle to freely move between your email and calendar without returning to the Start screen. Outlook Mail includes customizable Swipe Gestures, letting you swipe right or left to take actions like delete, flag, move or mark as read/unread. Also check out the new email authoring experience. Outlook Mail leverages the familiar capabilities of Word to create a richer email experience. You can do formatting tricks like inserting tables, adding pictures and using bullets and text. Outlook Mail and Outlook Calendar connects to Office 365, Exchange, Outlook.com, Gmail, Google Calendar, Yahoo!, IMAP, POP and other popular accounts.

Please note that to add or remove accounts in Outlook Mail and Outlook Calendar, you do so within these apps. The Email + accounts page has been removed from the Settings app.

New Phone and Messaging apps: You’ll see our new Phone and Messaging apps in this build. Give them a try and let us know what you think. The Messaging app has a new visual design. You can also easily upgrade from a messaging conversation to a voice call with one click of the phone icon in the new app bar.

Note: If you are updating a phone from Build 9941 – please see below for a known issue regarding MMS that will require you to go use the Windows Phone Recovery Tool to roll back to Windows Phone 8.1 first and upgrade to this build in order to have MMS working on your phone.

New People app: The new universal People app has a new visual design but will continue to be the comprehensive list of all your contacts across the services you care about such as Exchange, Outlook.com, Gmail, Facebook, etc. You’ll be able to easily manage all your contacts and quickly connect with them.

New Maps app: The first preview of our new universal Maps app on phone is now available. Maps offers you the features and tools you need to explore and navigate the world. This includes the best maps, aerial imagery, rich local search data, and voice guided navigation experiences from both Bing Maps and HERE maps, integrated together for the first time into a single app for Windows.

Updated App Switcher: Check out the updated app switcher by pressing and holding the back button on your phone to see your recently used apps. We’ve added support for landscape when invoked from an app being viewed in landscape. For large phones like the Lumia 1520, we’ve introduced a new grid layout so you can be more efficient at switching between apps. And we’ve extended the length of recently used apps to 15.

Some things we’ve fixed

  • We’ve updated the keyboard layout based on your feedback. The keyboard layout now has period, comma and emoji keys on first page of keyboard. Language switching is enabled by press-and-hold on the &123 key. There is also an option to replace the emoji key with the language switching key.
  • We’ve fixed the Cortana icon resolution so it now scales with tile size.
  • We’ve fixed the issue where the Photos app would fail to launch periodically when attempting to add a photo attachment to an email, OneNote or Facebook item.
  • We’ve fixed the issue where the Microsoft Band wouldn’t sync with your phone after upgrading to Windows 10.
  • The Photos app’s tile will now pick up the phone’s theme color before it’s launched and then start showing pictures from your collection including OneDrive in the Live tile.

Here are some known issues

This is preproduction software going out to the Fast ring – so you should expect to see some bugs. The list below are some of the ones that we thought you should know about up front, and it’s worth reading carefully. We’re working to fix all of these in future builds.

  • There might be situations in which auto-upload of your Camera Roll to OneDrive may not be working. Please be sure to back up your photos especially if you need to use the Windows Phone Recovery Tool to go back to Windows Phone 8.1.
  • The Office Hub has been removed from this build. You won’t be able to open Word, Excel, PowerPoint or OneNote files in this build. Preview versions of the universal Office apps will be available in the coming weeks.
  • All Bluetooth-based interactions with Cortana are not working in this build because we’re reworking how Cortana interacts with Bluetooth. This includes dictating and reading text messages, initiating searches and chit-chat, and all system-level control (such as playing music, launching applications, or navigating settings.
  • After upgrade, some apps that have been installed onto a SD memory card will fail to launch. To fix this, uninstall and reinstall the apps.
  • About 1% of the time, incoming phone calls may not play a ringing sound.
  • Call + SMS filtering will not work after upgrade.
  • For people upgrading their phone from Build 9941, there is a bug in which your phone’s MMS settings will be lost after upgrade. The new Messaging app doesn’t yet have the ability to re-enter these settings. You will need to use the Windows Phone Recovery Tool to go back to Windows Phone 8.1 and then upgrade to this build to get MMS working again.
  • Also for people upgrading their phone from Build 9941, the tiles on your Start screen for the Camera and Photos apps may be missing or corrupt. You will have to unpin any corrupt tiles and re-pin the apps to your Start screen.
  • On some phones, due to a scaling bug the dismiss button won’t be visible when an alarm is triggered. To stop your phone from “alarming “just touch the arrow and swipe up on the notification and off the screen to end the alarm.
  • On phones with 512MB of memory, apps can randomly crash due to an issue with memory management.
  • Flight mode cannot be enabled.
  • Data connections can’t be disabled.
  • You may need to re-pin the Phone app after upgrade.
  • The Insider Hub is now included on Phone but may fail to launch on some phones.

I’m very excited to get this build out to all of the eager Windows Insiders who have been waiting since our first preview build to try Windows 10 on their devices. We are still very much in the thick of development and this build still has some rough edges, but there is also a lot to be excited about here as well.

I hope that you’ll try it out and send us feedback via the Feedback app with your problem reports and suggestions.


Have questions and comments? Head over to the Windows Insider Program forums.

Updated April 21, 2015 2:48 pm