Raspberry Pi OS
Install Flatpak
A flatpak package is available in Raspberry Pi OS (previously called Raspbian) Stretch and newer. To install it, run the following as root:
sudo apt install flatpakAdd the Flathub repository
Flathub is the best place to get Flatpak apps. To enable it, run:
flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepoImportant note: It is recommended to use Raspberry Pi OS 64-bit as newer applications are more likely to be available for that platform only.
Restart
To complete setup, restart your system. Now all you have to do is install apps!
Note: graphical installation of Flatpak apps may not be possible with Raspberry Pi OS.