Mobian is an open-source project aimed at bringing Debian GNU/Linux to mobile devices.




GrapheneOS is described as 'Privacy and security focused mobile OS with Android app compatibility developed as a non-profit open source project. It's focused on the research and development of privacy and security technology including substantial improvements to sandboxing, exploit' and is a very popular Mobile OS in the os & utilities category. There are more than 25 alternatives to GrapheneOS for a variety of platforms, including Android, Android Tablet, Linux, Linux Mobile and Android SDK apps. The best GrapheneOS alternative is Android, which is both free and Open Source. Other great apps like GrapheneOS are LineageOS, CalyxOS, iodéOS and postmarketOS.
Mobian is an open-source project aimed at bringing Debian GNU/Linux to mobile devices.




Distributed microkernel OS with AI and edge computing capabilities for smartphones, wearables, TVs, tablets, and IoT; features multi-layered architecture, custom device kernels, Linux ABI compatibility, seamless interaction, and resource sharing across devices.

Paranoid Android provides a unique experience and ultimate customization for your Android device.



CrDroid is a customized fork of Android based on LineageOS bringing a lot of custom features ported from others great roms out there.



AXP.OS is a more private and more secure aftermarket mobile operating system based on AOSP & LineageOS.
Project Elixir basically offers a minimal UI enhancement & close to Stock Android ROM with great performance, security and stability. Your experience while using Project Elixir will be butter smooth without compromising the quality of the Android experience.


The new operating system from OnePlus, based on Android. OxygenOS is light and essential with subtle, useful features.



Ubuntu Touch is made and maintained by UBports. It is a free and open source mobile OS for you! Meanwhile we care about your privacy and freedom.


Havoc-OS is an after-market firmware based on Android Open Source Project, inspired by Google Pixel with a refined Material Design UI. We offer a smooth and stable experience for your device with a selected set of amazing features that provide an exceptional user experience.



Xiaomi HyperOS is a proprietary operating system developed by Xiaomi. It's designed to provide an enhanced user experience through its unique features and functionalities. The system integrates seamlessly with Xiaomi's wide range of devices, creating a unified and...

CarbonRom is an aftermarket firmware based on the Android Open Source Project.
Features:
PIE Halo AOKP Ribbons Comprehensive speed enhancements, including Linaro -O3 and processor-specific optimizations Unofficial Voodoo Sound support on Note 2 and i9300 de.



BlissRoms, an open-source operating system built upon Android Open Source Project, that offers a harmonious blend of customization, options, and security features. With a commitment to delivering pure bliss in every build, it brings with it a world of limitless possibilities.



Not secure. Firmware is mostly untouched and the software is not checked for integrity etc. Android is way more secure.