Firefox OS (project name: Boot to Gecko, also known as B2G) is a discontinued open-source operating system made for smartphones, tablet computers, smart TVs, and dongles 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 2014. 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 discontinued B2G OS and Acadine Technologies' H5OS as well as KaiOS Technologies' KaiOS and Panasonic's My Home Screen. History Firefox OS was publicly demonstrated in February 2012, on Android-compatible smartphones. By December 16, 2014, fourteen operators in 28 countries throughout the world offered Firefox OS phones. On December 8, 2015, Mozilla announced that it would stop sales of Firefox OS smartphones through carriers. Mozilla later announced that Firefox OS smartphones would be discontinued by May 2016, as the development of "Firefox OS for smartphones" would cease after the release of version 2.6. Around the same time, it was reported that Acadine Technologies, a startup founded by Li Gong (former president of Mozilla Corporation) with various other former Mozilla staff among its employees, would take over the mission of developing carrier partnerships, for its own Firefox OS derivative H5OS. In January 2016, Mozilla announced that Firefox OS would power Panasonic's UHD TVs (as previously announced Firefox OS "would pivot to connected devices"). In September 2016, Mozilla announced that work on Firefox OS had ceased, and that all B2G-related code would be removed from mozilla-central. Project inception and roll-out Commencement of project On July 25, 2011, Andreas Gal, Director of Research at Mozilla Corporation, announced the "Boot to Gecko" Project (B2G) on the mozilla.dev.platform mailing list. The project proposal was to "pursue the goal of building a complete, standalone operating system for