How to "Jailbreak" an Amazon Fire TV Stick
Ever dreamed of getting Android apps from outside the official Amazon Appstore on your Fire TV device? You can, in a process often called “jailbreaking.” It’s easy to perform, and it’s not the illegal or hacky process it sounds like.
Amazon Fire Amazon Appstore Difference Between Jailbreaking Allow Sideloading Enable Unknown Sources From Unknown Sources
Source: howtogeek.com