Open-source mobile operating systems
6 mobile operating systems whose code is public under an OSI-approved license, rated for privacy with evidence. Picks first, then by score.
GrapheneOS Grade B Our pick
A privacy and security focused mobile operating system with Android app compatibility, developed as a non-profit open source project for Google Pixel devices.
Released under OSI-approved licenses, inherited from upstream projects or MIT for its own projects. Source code
LineageOS Grade C Our pick
A free and open source operating system based on Android that supports many phones and tablets, including ones no longer updated by their manufacturers.
Based on the Android Open Source Project, mostly Apache-2.0. Source code
CalyxOS Grade B
An open source, de-Googled Android OS with optional microG, a built-in firewall and encrypted backups.
Based on the Android Open Source Project, mostly Apache-2.0. Source code
iodéOS Grade B
Android-based mobile operating system derived from LineageOS, without Google apps, with microG and a built-in blocker that filters ads and trackers across all apps.
Based on LineageOS under Apache-2.0; the iodé blocker app is AGPL-3.0. Source code
Nura Grade B
Linux distribution for phones and other mobile devices, formerly named postmarketOS, based on Alpine Linux and aiming to keep devices usable long after vendor support ends, with a choice of mobile interfaces.
GPL-3.0 for the project's packaging and tools, on top of open source Alpine Linux packages; some devices need proprietary firmware. Source code
Ubuntu Touch Grade C
Mobile operating system for phones and tablets developed by the UBports community, using the Lomiri interface and running on devices originally shipped with Android.
Mostly GPL-3.0 and LGPL; device support relies on proprietary Android vendor drivers. Source code
Compare all 10 mobile operating systems, open source or not.