In iOS 18.1, there is a new option to set a ”Primary” email address in the Settings app, which means it is easier to change the main email address associated with your Apple Account. The Primary email address is the one that is visible to other people when collaborating on and sharing documents, sending calendar invites, and more.
Källa: iOS 18.1 Includes Option to Set ’Primary’ Email Address and Change iCloud Email
