We’re retiring the Windows Phone app for Microsoft Teams. Here are the key dates to remember:
July 20, 2018: The app will no longer be available for download in the Microsoft Store.
October 20, 2018: The app will be retired and you'll get an error message if you try to use it.
To get the full picture, see this article.
What should you do?
You can still connect to Teams on the web using the browser on your Windows Phone. Just go to https://teams.microsoft.com.
If you’ve got an iOS or Android device, keep using the Teams app there! And the Teams desktop apps for Windows and Mac are updated regularly. Download your preferred app.