Sprint (NYSE: S) has followed T-Mobile (NASDAQ: TMUS) by taking steps to allow customers to put more than one number on a single device.

The No. 4 U.S. wireless carrier has picked Movius' cloud-based platform to offer the service. Sprint expects the multi-number, single-device service to launch in the first half of 2017.

"Movius' patented technology and cloud-based platform will bring incredible value to our customers," said Sprint Business President Jan Geldmacher in a press release. "We believe a second line on devices has enormous benefit to both business and their employees. It will provide convenience to individuals, while business entities will have the oversight and analytics needed to assure that employees are being compliant with company policies."

T-Mobile announced this first

It's easy to see why business or even personal users would want this technology. A corporate customer could offer its users separate numbers for different business needs. An individual could use the technology as a way to keep work and personal apart or for a variety of other reasons including a way to hold onto a number while eliminating a land line.

T-Mobile announced a similar service in early December. As part of its new DIGITS offering, the No. 3 wireless carrier will offer customers the ability to put multiple numbers on a single device. DIGITS has already launched as a beta test, and it will fully roll out later this year.

Why is this important?

Having more than one number connected to a single phone can be a money saver. T-Mobile said in its launch announcement that more than 30 million Americans carry multiple devices.

"So if you juggle identical phones with work and personal numbers, you can stop paying for two devices, two plans and two times the network access fees -- a practice that costs U.S. wireless customers an extra $10 billion every year," said the company.

It's easy to see why people would want this option, and Sprint and T-Mobile are smart to offer it ahead of their bigger rivals. It's very hard to provide something different in the wireless space, and for now, this is a useful, differentiator that might lure some AT&T and Verizon customers to make the switch.

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Daniel Kline has no position in any stocks mentioned.

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