WASHINGTON — It just got a little easier to swap cellphone providers.

President Obama has signed a bill making it legal once again to unlock a cellphone without permission from your wireless provider, so long as the service contract expired.

Copyright law prohibits circumventing digital locks on technological devices. But for several years, cellphones were granted an exemption by government copyright lawyers. But the federal copyright office let that exemption lapse in January 2013, infuriating consumer advocates who say phone owners should be able to do whatever they want with a device once a contract expires.

The law, which applies only to cellphones and not other wireless devices like tablets, lets people unlock their phones or hire a third party to do it for them.