Firefox OS (codenamed Boot to Gecko, also known as B2G) is a discontinued open-source operating system – made for smartphones, tablet computers and smart TVs – designed by Mozilla and external contributors. It is based on the rendering engine of the Firefox web browser, Gecko, and on the Linux kernel. It was first commercially released in 2013.
Firefox OS was designed to provide a complete, community-based alternative operating system, for running web applications directly or those installed from an application marketplace. The applications use open standards and approaches such as JavaScript and HTML5, a robust privilege model, and open web APIs that can communicate directly with hardware, e.g. cellphone hardware. As such, Mozilla with Firefox OS competed with commercially developed operating systems such as Apple's iOS, Google's Android, Microsoft's Windows Phone, BlackBerry's BlackBerry 10, Samsung's/Linux Foundation's Tizen and Jolla's Sailfish OS. In December 2015, Mozilla announced it would stop development of new Firefox OS smartphones, and in September 2016 announced the end of development. Successors to Firefox OS include the community-developed B2G OS (no longer maintained), Acadine Technologies' H5OS (now also discontinued), KaiOS Technologies' KaiOS and Panasonic's My Home Screen.