Hello all, today I’m very happy to announce that the new Windows 10 Technical Preview Build is available now for phones. We will inform the release date of Windows 10 for PC soon.

In this post, you will know which devices is supported this time, how to update your Lumia to Windows 10, what’s new in this build 10051 and some issues that we’re already fixed.

Windows 10 for phones Build 10051
Windows 10 for phones Build 10051 is available now

As I’ve informed about the new Windows 10 build for phones and some leak of it also, 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.

For today, all Lumia devices will get Windows 10, except Lumia 930, Lumia Icon and Lumia 640XL.

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.

Although Lumia 930 and Lumia Icon are excluded from the Windows 10 preview today due to a scaling issue, users can get Windows Phone 8.1 Update 2.

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 520
Lumia 525
Lumia 526
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

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.

How to update?

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.

If your device is still in Windows Phone 8.1, read the instruction here.

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.