Unlocking a cell phone is officially legal again.

On Friday, President Obama signed the "Unlocking Consumer Choice and Wireless Competition Act" (S.517) into law.

The new law repeals a 2012 decision by the Library of Congress that made cell phone unlocking a violation of the 1998 Digital Millennium Copyright Act. The DMCA, which prohibits Americans from "circumventing" technologies that protect copyrighted works, gives the Library of Congress the authority to grant exemptions. Last year, the Library of Congress opted not to renew the DMCA exemption for cell phone unlocking, which it had granted in 2006 and 2010.

Unlocking a cell phone is important for consumers who travel abroad and for those who want to take their devices to other carriers. The reason why is that most devices sold in the US through wireless operators have a software lock on them which prohibits them from being used on another operator's network. The ban on unlocking put a roadblock in the way for consumers who wanted to use their devices on other networks.

Many politicians and consumer groups have said the new law will help promote consumer choice in the wireless market, since it allows consumers to take their cell phones to other carriers. But the reality is that the benefits may be slightly overstated as there are still significant technical barriers to taking any cell phone to any wireless carrier in the US.

CTIA, the wireless industry's lobbying group, applauded the new law but also pointed out this distinction.

"Even though the vast majority of Americans enjoy upgrading to new devices once their contract terms are fulfilled, we recognize that some consumers may want to unlock their devices to move to another carrier," Jot Carpenter, vice president of government affairs at CTIA, said in a statement. "Like the voluntary commitment CTIA's carriers entered into last December, this bill enables that process. Users should keep in mind unlocked does not necessarily mean interoperable, as carrier platforms and spectrum holdings vary."

Still, many agree that decriminalizing cell phone unlocking is a step in the right direction. Earlier this year, the Federal Communications Commission brokered a deal with major wireless carriers to allow people to unlock their cell phones.

"This new law is a positive development that addresses the issues that triggered unlocking concerns in the first place," FCC Chairman Tom Wheeler said in a statement. "When the wireless industry worked with the FCC on a voluntary agreement to unlock devices when consumers' contracts have been fulfilled, they took an important step forward. The president's signature today makes greater consumer choice the law of the land."