How to setup and use call relay on your MacCall relay, part of Apple's Continuity features, lets you answer and place calls from your iPhone using your Mac, without having to scramble to find your phone. Because call relay uses the same phone number, carrier, and plan as your iPhone, the person on the other end can't tell the difference. It also shows you the caller's number, contact picture, and more, so you don't lose out on any features. Best of all, it's really easy to use — here's how!
Continuity call relay requirements
In order for call relay to work, both your iPhone and Mac need to be:
Running iOS 8.1 or later on iPhone, OS X Yosemite or later on Mac.
Connected to the same Wi-Fi network.
Logged into the same Apple ID (iCloud account).
How to enable or disable call relay on the Mac
Launch FaceTime from the Dock or Finder.
Click on FaceTime in the top menu.
Click on Preferences...
Click the checkbox next to Calls from iPhone.
To disable Call Relay, just repeat the same steps at uncheck the box.
Bear in mind tha...
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How to setup and use call relay on your Mac