The Bellevue, Washington-based company has some 8,500 active U.S. locations for its hotspots, in stores, hotels, and airports.

Robert Dotson, T-Mobile USA CEO and president, said in a statement that people are looking to drop their home landline phone and just use their cell phone, but "they don't want to use all their wireless minutes talking from home." This "first-of-its-kind service," he said, allows them to use only their mobile phone, without incurring extra minute charges.

The company said HotSpot@Home addresses the complaints of many cell phone users about poor in-home coverage. About 27 percent of all wireless minutes are currently used inside a home, T-Mobile said.

Only Two Handsets

The service currently only works with two handsets, the Samsung t409 and the Nokia 6086. Each is $49.99 with a two-year contract. The service itself costs $9.99 monthly for a single line, added to a T-Mobile voice plan, or $19.99 for as many as five lines, and includes unlimited Wi-Fi calling.

Customers can use their own Wi-Fi router, or optimized routers from T-Mobile's partners, D-Link and Linksys. The T-Mobile-supplied routers are free with a rebate, and are designed for simple setup, enhanced battery life for the handset, and high quality of voice calls, according to the phone company. They work on the customer 's existing broadband connection.

"This program makes sense for T-Mobile," said Bill Ho, an analyst with industry research firm Current Analysis, because T-Mobile doesn't have a wireline infrastructure to preserve and it helps T-Mobile in coverage. "What," he asked, "do they have to lose?"

He said it was unlikely that AT&T Wireless or Verizon Wireless would want to do this, because it would "cannibalize" their wired infrastructure.

Start on Wi-Fi, Billed as Wi-Fi

For the user, Ho noted, the $10 monthly add-on for the service is "not a bad price point," although the limitation of only two compatible phones is restrictive. He said that there are technologies being developed that could greatly increase the number of compatible handset models.

An additional benefit, he said, is that "if you originate a call on Wi-Fi and you walk around and it's seamlessly handed off to cell, you're still billed at the $10-all-you-can-eat Wi-Fi rate." But, if you start on the cellular network and then walk into Wi-Fi, your minutes are being counted as cell. So, users who notice they're being carried by a cellular network can sign off and call back when they reach a Wi-Fi connection.

There have been similar programs in Europe, Ho said, that use Bluetooth access points for the connections. T-Mobile started a pilot for HotSpot@Home in Seattle last year.