7UP might be the uncola, and T-Mobile is, in many ways, now trying to showcase itself as the "un-carrier" in a wireless world crowded by three bigger dogs.

The company, currently sitting in a festive fourth place behind AT&T, Verizon, and Sprint (even with its pending acquisition of MetroPCS, which awaits stockholder approval), has officially flipped the switch on one of its more ambitious plans to court new subscribers: The complete elimination of wireless contracts. You know, those, "you're locked in for x amount of time" deals that you often sign when looking to upgrade your old and busted phone on the cheap.

So how, then, does this process work in T-Mobile's new world?

First, interested purchasers of new smartphones will still find they're able to get a deal on their new devices—sort of. While T-Mobile isn't requiring a contract for one to pick up a discounted phone, the company will nevertheless add a surcharge to one's monthly bill for a set amount of time depending on the price of the phone selected. Avoiding this fee is easy, provided one pays the full price of the phone up front.

Removing that part from the equation for a moment, T-Mobile's base plan for unlimited talking and texting now starts at $50 per month–and includes 500MB of high-speed data. Technically, it appears as if all of T-Mobile's plans include unlimited data, with the catch being that T-Mobile throttles the data rate down to measly 2G speeds once one exceeds one's paid-for allotment of "high-speed data."

T-Mobile's next plan jump up to 2GB of data for an additional $10 per month. After that, $70 per month gets you truly unlimited talk, text, and high-speed data. You can add a second phone line for $30 per month, and each additional line after that costs $10 per month. There are no caps and no overages, though users will be throttled if they exceed their allotted data.

The unveiling of T-Mobile's contract-free plans comes in advance of a Tuesday press event where the company is expected to discuss this and other ways in which it plans to step up as more of a competitor in the wireless markets. That includes the likely discussion of T-Mobile's 4G LTE rollout — a stumbling block for those looking for the fastest mobile speeds (or some of the newer devices to use on T-Mobile's network, like Apple's iPhone).

For more, check out T-Mobile LTE Speed Tested, Sort Of and OpenSignal Finds T-Mobile LTE in 8 Cities.

Editor's Note: This story was updated March 26.