If you see 'app needs to be updated' after updating to iOS 14.5

If you update to iOS 14.5 and an app displays a message that it needs to be updated, your device administrator may need to update the app.

Some apps need to be updated to work with iOS 14.5. If you open an app and see a message that it needs to be updated, update the app to the latest version. If you can't update the app and your device uses apps assigned by mobile device management (MDM), your device administrator may need to update these apps before you can open them on your device.