An unlocked phone is one not tied down to a specific carrier network. If you want to use an unlocked phone, what are the practical implications? Who sells unlocked phones? What carriers let you unlock theirs and activate others? BYTE explores these issues and tells you why you might want an unlocked phone and how you'd go about buying one and getting service for it.
Consumers can Purchase an Unlocked Phone
In many cases, consumers can purchase unlocked phones outright. You can purchase them from a number of different sources, including importers. And many do. This opens up a LOT of options related to carriers and pay-as-you-go-plans. For example, you can get on a plan without purchasing a phone, but carriers don't always make it easy, nor do they like to do this.
The one thing you have to remember when working with a new unlocked phone i.e. one you're purchasing for use right now is you're not (necessarily) going to pay for the device over the life of your contract but your up front costs will be higher. However, you will likely save money over the usable life of the device.
There's a big problem with moving a phone between networks, especially in the U.S.: Different carriers use different network technologies and frequencies. You can't move a CDMA phone (from Verizon, for instance) to a GSM network (like T-Mobile's). Even LTE networks aren't directly interchangeable. As a general matter, unlocked phones work best with GSM phones on GSM networks. In such cases it's a fairly simple matter of swapping SIM cards. LTE networks also use SIM cards, but the networks use different bands and frequency ranges.
Apple unlocked iPhone won't work on CDMA, so don't think you'll take it to Verizon. Apple's site is somewhat cryptic about LTE support; on the one hand, it says it "only works on supported GSM networks," on the other hand it points you to a list of carriers that support iPhones on LTE. The intimation is that it can be programmed to work on different LTE networks, but we haven't tried this and don't know if it can be done.
The unlocked iPhone only works on supported GSM networks, such as AT&T in the U.S. When you travel internationally, you can also use a nano-SIM card for iPhone 5 from a local GSM carrier. The unlocked iPhone 5 is model A1428. For details on LTE support see www.apple.com/iphone/LTE. The unlocked iPhone will not work with CDMA carriers such as Verizon Wireless or Sprint. Learn more about the unlocked iPhone
Be that as it may, all four major carriers have slightly different, and in some cases complex policies regarding unlocked phones. Overall GSM networks tended to be more willing to work with customers with unlocked phones probably because SIM cards make changing carriers relatively straightforward. Because CDMA technology makes phones less reliable when brought to another carrier, CDMA network providers are willing to work with unlocked phones, but cautioned us that there may be problems. We talked with the four big carriers in the U.S. about their specific policies.
A spokesperson at GSM-based AT&T said in an email to BYTE that the carrier allows unlocking a smartphone under the following circumstances: "...if a customer's account is in good standing, and that the device can't be associated with a "current and active term commitment." The spokesperson went on to clarify, "[the customer] needs to have fulfilled their contract term, upgraded under one of our upgrade policies or paid an early termination fee. The statement also said AT&T is "happy" to sell a SIM card to a customer with an unlocked GSM phone.
An email sent from AT&T as part of the official unlocking process.
Interestingly enough, CDMA-based Verizon doesn't lock its phones in the U.S., a spokesperson told BYTE in an email. Internationally, it's another story. Verizon has "specific polices for international unlocking," the spokesperson said, and "is prohibited from locking phones in the 700Mhz spectrum." The issue, according to the company, stems from copyright law and "...isn't something that will change our policies or practices at all we don't lock our phones domestically..." the spokesperson wrote.
A spokesperson at GSM-based T-Mobile told BYTE in an email that customers should thoroughly understand the company's policy. Although different policies and specific details apply for each type of plan, generally customers who wish to unlock their phones must be in good standing, have paid for their device and have fulfilled any contractual obligations to the company.
With regards to bringing unlocked phones to the T-Mobile network, the company said it welcomes the practice but recommends customers contact their phone's manufacturer to request the unlock code for their device, according to the spokesperson.
Sprint, a CDMA network, locks phones it sells, claiming that the company does so to "... protect many of a device's features and functions against tampering and unauthorized re-programming," a spokesperson said in an email to BYTE. Sprint will provide customers with the device's "Master Subsidy Lock Code," a string of numbers required to unlock a device, once a contract term is complete and so long as the customer is in good standing.
Sprint is reluctantly willing to activate devices that are unlocked and from another network, the company spokesperson said, adding the caveat that while voice may function, other features and services may not.
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