Firefox is a web browser developed by Mozilla. There have been concerns about the future of Firefox, but it is still being actively developed for desktop (Windows, macOS, Linux) and mobile versions for iOS and Android. Firefox has undergone several updates since its initial release in 2004, with the development and release model changing into a "rapid" one from version 5 onwards. In 2020, Mozilla had two rounds of layoffs, and its lucrative search deal with Google, which is responsible for the vast majority of its revenue, is set to expire in 2023. However, Mozilla is doing better than ever financially, with its revenue from non-Firefox products up by 125% and its overall revenue up by 25% . Google has also continued to pay Mozilla for Firefox, despite the dominance of its own Chrome browser. There have been criticisms that Firefox has become bloated, ugly, and slow, but it is still being used by many people.