I am running Ubuntu 18.04 in Virtualbox. I am trying to install KiCad and followed steps given here: https://kicad-pcb.org/download/ubuntu/
sudo add-apt-repository --yes ppa:kicad/kicad-5.1-releases sudo apt update sudo apt install --install-recommends kicad # If you want demo projects sudo apt install kicad-demos
But after doing this I am getting KiCad 4.0.7 installed in my ubuntu instead of 5.1.6.
Earlier there was no PPA compiled for 18.04 but there was for 20.04 that’s why it was not working and installing old KiCad.
Now KiCad team has released 18.04 compiled PPA as well so now using same commands we can get latest KiCad Installed.