CalyxOS is an Android-based mobile operating system focused on privacy and security. It provides an alternative to standard Android while reducing dependence on Google services.

GrapheneOS is an open-source mobile operating system based on Android with a strong focus on security and privacy. It is primarily developed and supported for Google Pixel devices.

LineageOS is a free and open-source Android distribution. It provides an alternative operating system for supported devices with additional customization and longer community-supported device lifetimes.

/e/OS is a privacy-focused Android-based operating system developed by the Murena community. It aims to reduce dependence on Google services while providing a familiar mobile experience.