A reader writes in, “I was wondering if you could explain what ‘jailbreaking’ means with regards to to iPhones and iPads. It’s common, but is it something I want to do?”

Jailbreaking refers to replacing or modifying the software on an electronic device (say an iPhone) in order to gain access to unauthorized apps, modify system features or to tinker with the way the device works. While it’s perfectly legal for phones, the danger is that installing jailbreaking software can change the way the device behaves and can void the warranty. But as long as you back up your data before trying it and have a way to restore your original software should something go wrong, jailbreaking isn’t as risky as it was when smartphones first hit the scene.

One recently released jailbreaking method called “evasiOn” for Apple devices was used 7 million times in the first four days it was introduced last month, according to Forbes.

Jailbreaking isn’t the same as “unlocking” a phone, which means hacking a phone to use on a different wireless carrier than the one from which it was purchased. That practice was made illegal last month when a legal exception allowing for wireless unlocking expired.

Email Omar Gallaga at ogallaga@statesman.com