I recently installed the Windows 10 November update and enabled Missed Call Notifications in Cortana settings. I own a Nokia Lumia 730 which runs on WP 8.1. I tried the new feature but I did not receive any notification on my laptop. Is this available only if both these run Windows 10 and Windows 10 mobile resp.
Honestly.. I am not sure.. But i\’m going to take a wild guess and say "Yes. Your phone will need windows 10 as well"