When you sync contacts with multiple accounts, you might have entries for the same person in more than one account. To help keep redundant contacts from appearing in the All Contacts list on iPhone, contacts from different accounts that have the same first and last names are linked and displayed as a single unified contact (unless they have different middle names). When you view a unified contact, the title Unified Info appears at the top of the screen. Unified contacts appear only in the All Contacts list.
The source accounts of a unified contact appear at the bottom of the screen, under Linked Cards.
View contact information from a source account: Tap one of the source accounts.
Unlink a contact: Tap Edit, tap , then tap Unlink.
Link a contact: Tap Edit, then tap and choose a contact.
If you link contacts with different first or last names, the names on the individual contacts won’t change, but only one name appears on the unified card. To choose which name appears when viewing the unified card, tap the linked card with the name you prefer, then tap Use This Name For Unified Card.
Linked contacts aren’t merged. Unless you edit a unified contact, the contact in the source account remains separate and unchanged. If you change information in a unified contact, the changes are copied to each source account in which that information already exists. If you add information to a unified contact, that information is added to the contact in each source account.
Linked contact information also appears at the bottom of an individual contact’s Info screen when it’s viewed in a specific source account (that is, not in the All Contacts list), which lets you see the Unified Info screen and the linked contact from each of the other source accounts.