Continuity features include Handoff, Phone Calling, Instant Hotspot, and SMS. You can start an email or document on iPhone, for example, and then pick up where you left off on your iPad. You can use your iPad or Mac to make and receive phone calls through your iPhone.
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Use Handoff with Apple apps such as Mail, Safari, Maps, Messages, Reminders, Calendar, Contacts, Pages, Numbers, and Keynote. Start a document, email, or message on one device and pick up where you left off on another device. You can also use Handoff with some third-party apps.