If you have an app targeting Windows 8 in the Windows Store, you can retarget it for Windows 8.1 in Microsoft Visual Studio 2013, then upload your new Windows 8.1 packages to your existing app targeting Windows 8. Customers who had previously downloaded your app on Windows 8 and later upgrade to Windows 8.1 will automatically get the version you submitted targeting Windows 8.1, and their settings, data, and in-app purchase history will be preserved.
After you’ve published packages targeting both Windows 8 and Windows 8.1, your app will be appropriately displayed in the Store so both Windows 8 and Windows 8.1 users have access to the version that’s best for them. Users running Windows 8 will see that there’s a version of your app targeting Windows 8.1, and be encouraged to upgrade, but if they remain on Windows 8 they can download the version of your app targeted for Windows 8 (and any further updated Windows 8 packages you may submit).
Note If you don’t upload Windows 8.1 packages, your app built for Windows 8 will still be available to customers running Windows 8.1 with its existing listing details and packages. Apps built for Windows 8 will run on Windows 8.1, but not the other way around.
Uploading app packages
In your Windows Store Dashboard, click the app tile. On the Packages page, you’ll be able to upload your new packages. The Windows Store Dashboard will automatically detect that these are packages built for Windows 8.1.
Note You must use the RTM version of Visual Studio 2013 to create your Windows 8.1 packages. Packages built using prerelease versions of Visual Studio 2013 will fail.
See Resolving package upload errors for help fixing any errors you encounter when submitting packages.
Updating app listing details
When you add your packages for Windows 8.1, the listing details from your current app listing will be copied over to the new listing to help you get started. You can review these and make changes as needed for your packages for Windows 8.1.
Note The information is copied, but it is then maintained separately. Changing information or adding new screenshots for the Windows 8.1 listing will not change your existing Windows 8 listing, or vice versa. If you want to make updates to the description for both Windows 8 and Windows 8.1, you need to do that in both places.
Keep in mind how your app will appear in the Windows Store for users on Windows 8.1. In particular, the first screenshot that you submit with your app may be used in Windows Store promotional layouts with Windows 8.1. Your app’s wide tile is also now used in screens such as Picks for you, so design your tile with that in mind.
Once your app is published, the Windows Store will automatically display the right listing to potential customers. Those running Windows 8 will see the listing associated with your Windows 8 packages, along with a note that a version targeting Windows 8.1 is available should they choose to upgrade. Customers running Windows 8.1 will see the listing you created for Windows 8.1.
When you import a Microsoft Visual Studio 2012 project into Visual Studio 2013 to make it a Windows 8.1 project, Visual Studio 2013 will automatically increment the version in a way that allows you to make some additional updates to your app targeting Windows 8 if you need to do that later. This is important because the version number of your first Windows 8.1 package must be higher than the version on your current and future Windows 8 packages. If you build your app package manually, it’s important to set the version number far enough ahead of the version number on your Windows 8 packages so that you leave enough room to increment the Windows 8 packages if you submit further updates.