Operating Systems

Alternative operating systems for old and new devices.

Linux-based

postmarketOS

Linux distribution for mobile devices
IMO: The full Linux experience for mobile devices. If you are looking to turn your old device into a Raspberry Pi++, this is it. Many thanks to the postmarketOS team and to all of the contributors for supporting (and mainlining!) hundreds of devices. Of course, current level of functionality for each device varies widely.
All devices that can at least boot postmarketOS

Ubuntu Touch

A whole mobile operating system experience, that is yours
IMO: Very smooth UI, solid basic apps, and very pleasant experience overall. Due to its design, running "regular" Linux GUI apps requires setting up an abstraction layer. Does not support VoLTE at all.
Supported devices

Droidian

Droidian is a GNU/Linux distribution based on Debian for mobile devices
IMO: The more "pragmatic" approach to mobile Linux. Droidian re-uses the same vendor-provided Android Linux kernels.
Droidian devices

Maemo Leste

A FOSS Linux distribution for mobile devices
IMO: Old-school OS from Nokia N900 days
Images

Android-based

Operating systems based on Android Open Source Project (AOSP)

Replicant

Replicant is a fully free Android distribution
IMO: For hardcode free software enthusiasts - there are no proprietary blobs, so much of the original device functionality does not work (built-in WiFi, GPS, 3D graphics).
Replicant 6.0 status

GrapheneOS

The private and secure mobile operating system with Android app compatibility
IMO: Android-as-it-should-be, clean, independent of (but can still use) Google services, and with multiple improved security features. Comes with original AOSP apps, which look outdated and might have less functionality than modern counterparts.
Which devices are supported?

LineageOS

A free and open-source operating system for various devices, based on the Android mobile platform
IMO: Clean Android with updated basic apps. Can run with or without Google Play Services, but does not officially support microG.
Devices

CalyxOS

CalyxOS is an Android mobile operating system that puts privacy and security into the hands of everyday users
IMO: LineageOS + microG, with many privacy features and privacy-focused default apps
Supported device models

DivestOS

A mobile operating system divested from the norm
IMO: A combination of LineageOS + microG and GrapheneOS hardening that supports a surprising number of older devices.
Device downloads

/e/OS

/e/OS is a complete, fully “deGoogled”, mobile ecosystem
IMO: Clearly leaning into privacy-as-a-service space. Professional, consistent appearance (facelifted FOSS apps), runs their own servers and services, and sells smartphones with preinstalled /e/OS.
Supported devices

iodéOS

iodéOS is an android operating system freed from Google trackers
IMO: Another commercial privacy-as-a-service product, which is essentially LineageOS + microG with FOSS apps and built-in blocking and parental controls.
Supported devices