Previous replies about the Fairphone 4 and ARCore have mentioned that you might be able to get it running with a patcher. - I just spent the afternoon looking into this, and here’s what I found so far:
- Information on how to install Magisk, a boot/image modification utility along with a thread in German, if that would be useful to you.
- A Magisk module to patch ARCore support into a phone
…Note that that ARCore patch is four years old at this point (!!!), but it’s developer was contributing to GitHub as recently as late December. I haven’t tried this, and it’s not for the faint of heart, but it’s a path forward.