Apple, Motorola, Alcatel, OnePlus and Huawei all sell unlocked phones. Unlocked phones generally come without contracts attached to them, except in Verizon's unique case, which came about as a result of an FCC ruling placing certain restrictions on its network.
Apple sells an unlocked version of its iPhone 6 smartphone, which, according to the reviewers at PCMag, works equally well on any of the four major U.S. carriers. Similarly, the Nexus line of Motorola phones, which it developed in partnership with Google, are available for purchase from the company free of any binding contract. Other notable unlocked, contract-free phones include the OnePlus One, the Huawei Ascend Mate2 4G and the Alcatel One Touch Idol 3.
Unlocked phones typically do not come with contracts because buyers pay full price for them. Contracts, as carriers use them, are a means to recoup the costs of the phone the carrier sells customers at a subsidized price. By paying full price for their phones, unlocked phone buyers essentially fulfill the contract before it even begins. In fact, paying the full price for the phone and settling any outstanding service commitments and the early termination fees are key requirements to become eligible to request to have a phone unlocked on networks such as AT&T. The only exception to this case as of 2015 is Verizon, which sells subsidized unlocked phones on contract to fulfill an FCC restriction applied to the company due to the design of its network.