@flatpakappsnews is a software for building, installing and running Linux apps. The Open Build Service now supports building @FlatpakApps bundles, so you can build your own! https://openbuildservice.org/2021/02/18/introducing-flatpak-builds/
Fosstodon is an English speaking Mastodon instance that is open to anyone who is interested in technology; particularly free & open source software.