Hello everyone, My name is Emmanuel Katto. I’m interested in customizing my Fairphone with custom ROMs. Has anyone successfully installed a custom ROM on their device? What are the pros and cons, and can you recommend any reliable ROMs for Fairphone?
Looking forward to your insights.
Thanks in advance!
Best,
Emmanuel Katto
Welcome to the community forum.
A good starting point would be our oslist.
You can find info about available custom ROMs on the different Fairphones there and then look for experiences with them following the tags given there (they look like the → oslist ← link, just with custom ROM names), which would lead you to a list of forum topics tagged as relevant for the respective custom ROM.
It’s a huge rabbit hole, be prepared with some spare time 
.
And the custom-roms tag will also help to filter and search
I have installed /e/os on Fairphone 2, 3 and 4 and can say that it is running very well. I don’t know any other custom ROMs. /e/os is based on lineage OS and officially supports Fairphones. See /e/OS - e Foundation - deGoogled unGoogled smartphone operating systems and online services - your data is your data
Good luck
Matthias
Hi,
I installed LineageOS on an FP2 and now on an FP4 (lineage-21.0). It works very well.
The only hitch, and I assume it’s the same with other custom rom’s, is that the bootloader is not locked after installing the rom…
The only rom (I think it’s the only one) that allows the bootloader to be locked after installation is GrapheneOS… but this OS can only be installed on Google Pixels (it’s actually rather odd that this totally ungoogled rom can only be installed on Google phones).
Most of the custom Android ROMs available for the FP4 (or one of the other Fairphones) will let you lock the bootloader, except for LineageOS 
See the installation instructions for e.g. CalyxOS, DivestOS, /e/OS, and iodéOS. The important part is to always check fastboot flashing get_unlock_ability right before locking it!!!
Thanks @AnotherElk for your help.
Thank you @hirnsushi