I created a quick tutorial on installing Home Assistant on a Rock Pi 4b+ for anyone that is interested.
It uses Ubuntu 18.04 as the OS. Uses the NVMe drive for the root filesystem (/boot is on the eMMC) which should alleviate SD Card failures people are seeing on Raspberry Pi’s.
This is a brand new setup for me so it has not been thoroughly tested other that the few days I’ve had this setup, but so far it is working great. Much faster than my Raspberry Pi 3+.
Thanks for the tutorial.
Do you know if the GPIO pins are compatible with HA ? I am looking to go to this solution because of the NVMe.
I’m not sure on that, but I think they are the same as the RPi. You might ask on the Radxa forums.
@lymkin what if I want to install everything on a SD card instead?
I know it will be slower, but then what steps shall I follow? 
@lymkin you mentioned that installation is on emmc.
Do I have to buy an emmc for the rockpi 4 in order to install Ubuntu?
Can I directly install Ubuntu on ssd?
Has anyone been running this board for awhile? Any current thoughts on this vs Pi 4B which are fairly scarce right now?
Latest method seems to be working (https://peyanski.com/how-to-install-home-assistant-supervised-official-way/#Home_Assistant_Supervised_method)
Assuming all the updates and docker installed, fetch latest OS agent from https://github.com/home-assistant/os-agent/releases/ get the aarch64 version, install with
sudo dpkg -i os-agent_1.2.2_linux_aarch64.deb
Then homeassistant supervised
wget https://github.com/home-assistant/supervised-installer/releases/latest/download/homeassistant-supervised.deb
sudo dpkg -i homeassistant-supervised.deb
I’ve selected raspberrypi4-64 as that seemed the closest option.
And that seems to do it…
is there a reason why you didn’t use qemuarm-64?