Microsoft Cortana apps for Android and iOS officially hit their failure on March 31, 2021. Microsoft’s voice assistant alternative to Google Assistant and Siri will continue to work on Windows 10.
As explained on Microsoft’s Cortana support page, the mobile app is no longer supported as of Wednesday of this week. Lists and reminders will no longer be available through Cortana apps on mobile. These reminders and lists are still accessible through Cortana on Windows 10 and the Microsoft To Do apps, available for Android and iOS.
The shutdown was originally announced in July 2020 (with evidence as early as November 2019), with the company confirming it would shift Cortana’s attention to an AI-powered assistant for Microsoft 356 apps.