I also tried to create a custom repo, using flatpak-builder then export the build to repo location, the I tried to sign the repo with a gpg key following this Maintaining a flatpak repository – Alexander Larsson
then at the moment of adding the repo to the client with this command
flatpak remote-add --gpg-import=example.gpg example http://example.com/repo
I get the following error:
error: GPG: Unable to export keys: GPGME: No data
the when I try to install an app build and exported to the repo I get
flatpak install --gpg-file=example.gpg example org.videolan.VLC
error: Unable to load summary from remote example: GPG signatures found, but none are in trusted keyring
not sure what I am doing wrong here,
Thanks Again