Cortana voice assistant for Android and iOS has been shut down, now enterprise focused
Microsoft has discontinued the mobile app for its Cortana digital assistant. This is a continuation of its redesign and increased enterprise focus.
The Android and iOS apps for Cortana have been both removed from the Google Play Store and the App Store as well as rendered inoperable. A Microsoft support article states the following:
"As of March 31, 2021, the Cortana content you created–such as reminders and lists–will no longer function in the Cortana mobile app, but can still be accessed through Cortana in Windows. Also, Cortana reminders, lists, and tasks are automatically synced to the Microsoft To Do app, which you can download to your phone for free."