T-Mobile said today it launched its first commercial high-speed wireless service in New York City, and plans to expand the service to 20 to 25 other major U.S. markets by the end of the year.

Nokia 3555 More Photos View Specs

Nokia 6263 More Photos View Specs

Samsung T819 More Photos View Specs

Samsung T639 More Photos View Specs

The new service, based on a high-speed technology known as HSDPA, will boost T-Mobile Web speeds by about four times initially, with another doubling of data speeds once the company comes out with a new HSDPA phone in the third quarter.

T-Mobile said its initial data speeds for the service will range from 200 kilobits per second (kbps) to 300 kbps from the current speed of 50 kbps to 80 kbps for customers already using its most advanced phones. Once the company comes out with a HSDPA phone, its average data speed will roughly double to 600 kbps, according to the company.

"The launch of our 3G network comes at a time when 3G phones and services are more affordable, capable and appealing to our consumer marketplace than ever before," said Cole Brodman, chief development officer, T-Mobile USA. "We benefit not only from the economic scale of 3G, but also from the extensive commercial experience of 3G in our European markets. Today, T-Mobile USA customers already have among the highest adoption of data and messaging services in the industry. Through our 3G network, we look forward to delivering a rich portfolio of new and meaningful services to enrich our customers' lives."

Web browsing and downloading content will be twice as fast with 3G on four phone models that T-Mobile started selling last year, Nokia's 3555 and 6263 and Samsung's T819 and T639.

In the coming months, T-Mobile plans to offer its first HSDPA device, along with new data-centric, all-in-one devices. While BlackBerry smartphones are an important part of T-Mobile's lineup, models with HSDPA likely won't be available until next year.