To install Flatpak on Pop!_OS 19.10 and earlier, simply run:sudo apt install flatpak
Add the Flathub repository
Flathub is the best place to get Flatpak apps. To enable it, download and install the Flathub repository file or run the following in a terminal:flatpak remote-add --user --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
To complete setup, restart your system. Now all you have to do is install some apps!
Note: graphical installation of Flatpak apps may not be possible with Pop!_OS 19.10 and earlier.
Flatpak support is built into Pop!_OS 20.04 and newer—no setup required!
If you are using an older version, you can refer to the instructions below.