Fairphone setup
Below are the steps I follow post standard installation of ubuntu touch on my Fairphone 4.
I've been using the fairphone 4 as a daily driver since April 2023, most recently with Ubuntu Touch.
Downgrade prior to installation
After initially purchasing the fairphone, while it was running android I had upgraded to android 12. Unfortunately the ubuntu touch installer is not fully working with Android 12 so I had to downgrade the phone to Android 11 by reinstalling a stock image before proceeding with the ubuntu touch installation.