If I have a standard IMAP mail account set as my default on an iOS device and I then attempt to send somebody an invetation from the Calendar app, what happens if the recipient doesn't have an Apple ID - how will the invitation appear to them?
No documentation that I could find online makes reference to this situation; the only things I could find were concerning sending invitations to existing Apple IDs (at which point a notification is generated on the device itself), or about using Exchange Accounts - which again works differently. My assumption was that Apple must send an email of some kind to the invitee, but I want to get it tested.