T-Mobile lets customers upgrade phones twice a year

(CNN) -- T-Mobile is making a bid to become the wireless world's "un-carrier," rolling out a plan that will let users update their phones up to twice a year for a modest fee.

That's a sharp departure from the traditional model for wireless companies, which usually requires customers to complete a two-year contract before they can get a new smartphone at the discounted rate that makes them affordable.

"At some point, big wireless companies made a decision for you that you should have to wait two years to get a new phone for a fair price. That's 730 days of waiting," said John Legere, president and CEO of T-Mobile US, in a written announcement.

"(That's) 730 days of watching new phones come out that you can't have. Or having to live with a cracked screen or an outdated camera," he added. "We say two years is just too long to wait."

The company's new JUMP! plan will cost $10 a month per phone and includes insurance for phones that are damaged, lost or malfunctioning. Some wireless customers already pay for such protection.

Customers can upgrade after being enrolled in the JUMP! program for six months.

At a New York event, T-Mobile also announced an expansion of its 4G LTE network, which it says will reach 157 million people in 116 metro areas across the United States.

The announcement is part of T-Mobile's newly aggressive approach as the carrier tries to move up from fourth place in market share in the United States. It trails first-place Verizon, then AT&T and Sprint.

Research firm comScore says Verizon has about 31% of the market, followed by AT&T at 27%, Sprint at 16% and T-Mobile at about 13%.

In March, T-Mobile took another big leap, announcing that it would offer wireless plans with no contract. It also began selling the iPhone 5 for $99 in April.