Interacting with a user's Contacts database used to be, shall we say, "less than ideal". The AddressBook framework was great for it’s time, but it’s a bit past it's prime these days.

Contacts and Contacts UI are two new frameworks in iOS 9 (and OS X + watchOS) that make integrating Contact data into your app a breeze.

Here's how easy it is to search a user’s contacts and present one for viewing:

func presentContactMatchingName(name: String) throws {
    let predicate = CNContact.predicateForContactsMatchingName(name)
    let keysToFetch = [CNContactGivenNameKey, CNContactFamilyNameKey]
    let store = CNContactStore()

    let contacts = try store.unifiedContactsMatchingPredicate(
        predicate, 
        keysToFetch: keysToFetch
    )

    if let firstContact = contacts.first {
        let viewController = CNContactViewController(forContact: firstContact)
        viewController.contactStore = self.store

        presentViewController(viewController, animated: true, completion: nil)
    }
}

Also, Apple has officially deprecated AddressBook and AddressBookUI so now's the time to make the switch!