/e/ is described as 'fork of LineageOS that aims to be completely free of everything Google. Not only that, but there are a number of goals the developer has in mind for /e/ that more people feel are vital to a mobile operating system' and is a popular app in the OS & Utilities category. There are more than 25 alternatives to /e/ for a variety of platforms, including Android, Linux, Android Tablet, Self-Hosted solutions and iPhone. The best alternative is LineageOS, which is both free and Open Source. Other great apps like /e/ are Android (Free, Open Source), Ubuntu Touch (Free, Open Source), GrapheneOS (Free, Open Source) and Replicant (Free, Open Source).
postmarketOS (pmOS), is a touch-optimized, pre-configured Alpine Linux that can be installed on smartphones and other mobile devices. The project is at very early stages of development and is not usable for most users yet. We develop a sustainable mobile OS