The version history of the Android mobile operating system began with the public release of its first beta on November 5, 2007. The first commercial version, Android 1.0, was released on September 23, 2008. The operating system has been developed by Google on a yearly schedule since at least 2011. New major releases are usually announced at Google I/O in May, along with beta testing, with the stable version released to the public between August and October. From 2025, new versions were announced in the first quarter and shipped in the second quarter.