Android - Android is an open source mobile operating system initially released by Google in 2008 and has since become of the most widely used operating systems on any platform.
e.foundation /e/ - /e/ is a fork of LineageOS that aims to be completely free of everything Google.
PureOS - A user friendly, secure and freedom respecting OS for your daily usage
LuneOS - LuneOS is a free and open source mobile operating system that respects users’ privacy.
DivestOS - A mobile operating system divested from the norm.
CalyxOS - Privacy-focused operating system for smartphones based on Android and microG