AT&T plans NumberSync: One phone number for all your devices

Similar to Apple's Continuity feature, AT&T will eventually route calls and messages from your phone number to all of your connected devices including phones, tablets, smartwatches and perhaps cars.

The days of SIM cards representing a single phone number may soon be over. AT&T announced its plans to roll out NumberSync, a network level that links multiple connected devices to one number.

"We know you may not want a different phone number for your other devices. Since NumberSync operates in our wireless network, it is not dependent on a Bluetooth connection to your smartphone. Your devices don't need to be near each other and NumberSync will work even if your primary phone is turned off or disconnected from the network."

NumberSync won't be limited to phones and tablets.

The carrier made a point of mentioning wearables, such as smartwatches, as part of future NumberSync plans. It would even be possible to tie a connected car to a shared-device phone number so that you won't miss or can make calls on the road, even without a phone nearby.

To some extent, this sounds similar to Apple's Continuity feature. If you have an iPhone, for example, your incoming calls and messages can seamlessly be routed to nearly Mac computers and iPads. The difference here is that NumberSync won't be limited to a platform and the call routing takes place on AT&T's network, not over a Wi-Fi network or Bluetooth connection.

AT&T says it plans to launch NumberSync on its first device "fairly soon" with more to follow during the holidays, later this year.

It doesn't appear there will be an extra charge for NumberSync but you're not likely going to save money either: The carrier already charges add-on fees for each connected device you bring to an account.