I do not know what kernel you are using and if it is the one @Strit is referring to but I followed this to get it going on my pi4. It will say binder module isn’t available if things are not set up before hand. Of course you will need to have the right kernel with android specific modules enabled. They will be in the kernel and will not show up with lsmod.
Install anbox anbox-image-aarch64
sudo mkdir /dev/binderfs
sudo mount -t binder binder /dev/binderfs
sudo systemctl start anbox-container-manager.service
Then there should be an anbox icon to tap on to start anbox some where on your phone. It will say “Loading” for a while (guessing decompressing the image) before it shows the Anbox Application Manager. Anbox has issues opening some programs I installed so it has a way to go in development.
This has to be automated some how so it can be loaded at boot but I never got around to it. I was more concerned in testing my new pi4 kernels to see if anbox loaded. Some one suggested fstab but I would think a mount point would have to exist for fstab to mount on (but I have been know to be wrong. lol) so I am thinking of making a systemd .service file.
mkdir /dev/binderfs
mount -t binder binder /dev/binderfs
