Set the cellular number label, open the cellular network page in the setting interface of Apple mobile phone, select the number to set the label, click the cellular number label in the first row after entering the number page, enter the label setting page, and customize and edit the label name at the bottom of the page.
Set the content of the number label according to personal needs, for example, you can simply set the main card and the auxiliary card to distinguish; You can also set function labels, such as marking this card for calls between family members, or for communication between colleagues in the company, etc. Personally, I think it is of little use. I simply set up the main card and the auxiliary card.