I'm in love with my reMarkable Paper Pro. Bought i around christmas and still using it almost on a daily basis for reading and taking (meeting) notes.

One thing that bothers me is, that besides the official keyboard folio from remarkable there's no way of using an external keyboard. But turns out the RPPs wifi chip also comes with bluetooth. They just don't use it yet. But once you activated developer mode and got access via SSH you can activate it and connect external bluetooth keyboards. Here are the steps:

modprobe btnxpuart  # This loads the bluetooth kernel module
bluetoothctl show # 
systemctl stop bluetooth
chmod 555 /etc/bluetooth
systemctl start bluetooth
bluetoothctl # This starts an interactive shell

We turn on bluetooth and start searching for MAC addresses:

pair <mac address> # You will be prompted to enter a code for your keyboard
connect <mac address>
trust <mac address>

Bumm. You should be able to use your keyboard. For me the pairing proccess always takes a few attempts and it shows multiple codes but after a while it was working. Still hoping reMarkable will release soon an update with a nice UI for that.

Source: reddit