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January 22, 2013
Windows Phone Developer Blog

Now Available: Windows Phone SDK Update for 7.8

Today we are releasing the Windows Phone SDK Update for Windows Phone 7.8, an optional update that adds two new Windows Phone 7.8 emulator images to your existing SDK installation. These two emulator images should enable you to fully test how your Windows Phone 7.5 app’s Live Tiles will look and behave when they are run on a device running Windows Phone 7.8. New phones with Windows Phone 7.8 are beginning to ship, so it’s a great time to update your apps to take advantage of the new Live Tile experience and to reach the new markets that Windows Phone 7.8 makes available.

This blog post briefly covers what is included in the Windows Phone SDK update; I’d highly recommend that developers take a look at Thomas Fennel’s blog on how to ‘light up’ your 7.5 app in Windows Phone 7.8 and 8.0 for a technical overview of how to use the new emulator images.

What’s in the update


The Windows Phone SDK update adds the following capabilities to your machine:

  • Windows Phone 7.8 emulator: This OS image emulates your app running on a 512-MB device running Windows Phone 7.8 (build 8858)
  • Windows Phone 7.8 256MB emulator: This OS image emulates Windows Phone 7.8 (build 8858) running on a 256-MB device
  • If you’re running a Windows Phone SDK 7.1 installation, the update will also download and install the Windows Phone SDK 7.1.1 update onto your machine as part of the update
    (again, only applicable to Windows Phone SDK 7.1 installations)

Along with what is installed, it’s also worth calling out what isn’t in the Windows Phone SDK update:

  • The update does not change your existing Windows Phone OS 7.1 emulator images—you can still develop and debug your apps on a phone running the standard Windows Phone 7.5 image
  • There are no new APIs available to Windows Phone apps in Windows Phone 7.8

Most importantly, any Windows Phone apps that you build using the Windows Phone SDK (with this update installed) still target and run on Windows Phone 7.5. This update simply makes it easier to test how your apps appear on devices running Windows Phone 7.8.


After you install the Windows Phone SDK update and fire up your app in one of the new Windows Phone 7.8 emulators, you’ll immediately be greeted by the familiar minimalistic UI experience (all you have is Internet Explorer on the start screen) and Windows Phone 7 device skin. And after pinning your app to the start screen, you’ll also notice that 7.8 now provides the option to make your app’s tile smaller. By default, the OS simply shows a smaller version of your standard app tile. To customize the appearance of your small tile, you’ll need to do some additional work.

Live Tile options when running on Windows Phone 7.8

At a high level, Windows Phone 7.8 allows you to have your 7.5 apps behave much like apps do on Windows Phone 8 devices, allowing you to do the following on a user’s start screen:

  • Your app’s primary tile can have a customized small tile, support wide tiles, and also take advantage of the Flip tile template.
  • Secondary tiles can be enabled to take advantage of all three of the new tile templates (Flip, Iconic, and Cycle).

Taking advantage of the new tile options available in Windows Phone 7.8 uses the same reflection approach that folks have been using over the past few months light up their 7.5 apps on Windows Phone 8 (refer to the ‘lighting up’ your tiles on Windows Phone 8.0 topic on the Windows Phone Dev Center for details). The only difference is the version information specific to Windows Phone 7.8 (Version 7.10.8858—per the following screenshot).


Additional links for more information

The SDK update requires an existing installation of the Windows Phone SDK:

For further information on developing Windows Phone apps that light up on Windows Phone 7.8 and Windows Phone 8.0, you may find the following links helpful:

All of that being said, if you have a Windows Phone 7.5 app, I’d highly recommend you download the Windows Phone SDK Update for Windows Phone 7.8 today and start experimenting by using the new tile options in your app. And, as always, feel free to post comments and/or questions about the Windows Phone SDK update here.