CalyxOS and GrapheneOS are two of the most reputable custom ROMs for Android devices, focused on privacy and security. Both ROMs offer a range of features that allow users to take control of their device's data and prevent unauthorized access.
* **CalyxOS**: Developed by Calyx Institute, this open-source operating system offers basic security features to keep your user's data safe while also being as recognizable to stock Android. Like GrapheneOS, Calyx supports on-device encryption, regular security updates, and sandboxing apps in a "Work" profile.
* **GrapheneOS**: Developed by Daniel Micay, is a hardened Android-based operating system featuring enhanced sandboxing and secure element support. GrapheneOS's strong focus on reducing the Android attack surface by disabling unneeded features and services sets it apart from other privacy-focused operating systems including CalyxOS. But, may feature a steeper learning curve compared to CalyxOS.
* **Qubes OS**: Qubes OS is a security-focused operating system that compartmentalizes different tasks into separate virtual machines (VMs) called "AppVMs" or "qubes." This approach provides an additional layer of isolation, creating a more dynamic attack surface.
* **Tails OS**: Tails is a live operating system that leaves no trace on the host computer. It routes all internet traffic through the Tor network by default, protecting users' anonymity. Preloaded with privacy-focused applications, Tails OS offers a comprehensive solution for secure communication with a more device agnostic design.