To manage Flatpak (Flathub)

To manage Flatpak (Flathub):

REPOSITORIES
To see some commands of Flatpak:
flatpak remote-modify --help

To see installed Flatpak repos (Brief view):
flatpak remotes

To see installed Flatpak repos (Name only):
flatpak remotes --columns=name

To see installed Flatpak repos (In detail):
flatpak remotes --show-details

To add Flatpak-based repos:
sudo flatpak remote-add --if-not-exists [REPO-NAME] [REPO_URL]

To remove installed Flatpak repos:
sudo flatpak remote-delete [REPO-NAME]

RUNTIMES
To see installed Flatpak runtimes:
flatpak list --runtime

To remove Flatpak runtimes:
flatpak uninstall [APPLICATION_ID]

APPLICATIONS
To see all applications:
flatpak remote-ls flathub --app

To see the history of the Flatpak app:
flatpak history

To search the Flatpak app:
flatpak search [APPLICATION_ID]

To install Flatpak app:
flatpak install [REPO-NAME] [APPLICATION_ID]

To run the Flatpak app:
flatpak run [APPLICATION_ID]

To remove Flatpak app:
flatpak uninstall [APPLICATION_ID]

To fix the checksum problem during the installation of flatpak applications:
1) Open a terminal and type these commands:
sudo flatpak repair
flatpak repair --user
sudo flatpak uninstall --unused
sudo flatpak update --appstream

To remove useless data of a Flatpak apps:
sudo flatpak uninstall --delete-data

To update Flatpak apps:
flatpak update

To see Flatpak installed apps with library apps:
flatpak list

To see the Flatpak installed apps:
flatpak list --app

To fix the Flatpak inconsistencies:
flatpak repair