How to link Ausweisapp2 with Smartphone app

Question

I cannot link my Ausweisapp2 to the app on my smartphone (app for german eIdentity service).

Installed via snap:

sudo snap install ausweisapp2-ce

In the app, there are no available devices shown.

• The docs say the devices must be in the same "Wifi", but my computer has cable only.
• I have ufw enabled, but regarding firewall, the FAQ only talks about Windows and that it should work with default settings or the firewall would ask, which is not the case.

Answer 1

• The docs are wrong. Devices must be in the same network, Wifi or Cable is both working fine.

• The AusweisApp2 uses the same default port (24727) as defined in TR-03124-1. (see also)

  So, for ufw:

  sudo ufw allow 24727
  

  or more specific:

  sudo ufw allow in from 192.168.1.0/24 to any port 24727
  

  Change 192.168.1.0/24 to your subnet.

Then it works fine.