For some people, it is important to have multiple phones ring for one incoming call. This means that when a certain phone number is called, multiple devices will ring at the same time instead of just one. This article explains how to do this using your mobile provider or an app.
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Some mobile providers allow you to use your number with multiple devices. These services allow you to automatically forward incoming calls to all your devices, including your phone, smartwatch, or tablet.
AT&T NumberSync lets you use a compatible device to answer your calls, even when your phone is turned off or not with you. Two similar devices are T-Mobile’s DIGITS and Verizon One Talk.
The same feature may already be enabled on your iPhone or iPad. As long as the person is calling you via FaceTime, or you have hardware that meets the Continuity System Requirements for the iPhone Cellular Calls feature, you can answer the call on your other Apple devices, including your Mac.