Mirror screening
How can I tell if my screen is being mirrored
iPhone 7, iOS 15
Question marked as
You can drag down your Control Center (the one you got from drag down the top right of the screen) and click on the Screen Mirroring button (The one looks like two rectangle overlapping), you will see the device used to mirroring is checked and the button should appear blue if screen is being mirrored. While the mirroring is not active the button should be darken.