T-Mobile will free your number up for multiple devices

The Un-carrier wants to unlock your phone number.

T-Mobile on Wednesday launched a program called Digits, which will let customers apply their phone number to multiple devices, or create and combine multiple numbers onto a single device.

T-Mobile is the latest carrier to free up your phone number to multiple devices -- AT&T and Verizon offer similar capabilities -- a move that breaks the usual requirement to have a single number tied to a single SIM card. By allowing you to apply a phone number to other devices, you can be contacted on a connected smartwatch, tablet or PC.

Digits goes further than its competitors by letting you create multiple numbers and apply them on a single or group of devices. That's ideal if you want to create a temporary phone number for a Craigslist sale or if you're uncomfortable giving out your "real" number to someone you just met at a bar. The numbers can also be applied to phones running on different carriers, so businesses can create T-Mobile numbers and assign them to their employee's personal phones, regardless of the service.

"We route your call to whatever device carries your identity," Chief Operating Officer Mike Sievert said in an interview. "It's extremely disruptive."

Digits launched today as a beta program, and is free to use. T-Mobile plans to formally launch it as a service next year for a fee. Sievert declined to comment on the price, but hinted it would be "attainable."

AT&T offers a similar service called NumberSync, where your mobile number can be applied to multiple devices. It isn't available on every device, although it boasts support for nearly 30 phones, including Apple's iPhone.

There are also a number of online services that let you create numbers, think Google Voice or Viber. But with Digits, you get a real T-Mobile numbers that run through its network, which means it's prioritized over data calling services and takes advantage of features like HD voice.

T-Mobile is able to do this by creating a new identity management system that is separate from the SIM card. The network is smart enough to know that your ID is tied to multiple devices or numbers, and routes the call accordingly. Customers are able to manage numbers and devices through their online accounts.

T-Mobile Chief Technology Officer Neville Ray said the carrier had been working on the system for two years. "It can't be replicated very quickly," he said.

Sievert believes the ability to extend your number across multiple devices will be the key to opening up the market for new devices, from smartwatches to even secondary phones. He said some users could have a main phone for daily use, and switch to a more rugged device for the beach, or just stick with a smartwatch when out running.

Samsung partnered with T-Mobile to make sure Digit works out of the box for all phones starting with the Galaxy S6 and newer.

"Obviously manufacturers can see we're moving past the era where you want just one," Sievert said.