Installing apps

Software comes from Flathub, through Discover or one command. Apps are sandboxed, update on their own schedule, and are entirely independent of the system image.

Discover

Open Discover from the application launcher. Flathub is already configured, so search, click Install, and the app appears in your launcher. Updates for installed apps show up in Discover’s Updates page and never require a reboot.

Discover on Immos only offers Flatpaks — there is no other kind of software to install, so there is nothing to choose between.

From the terminal

The same thing, if you prefer typing:

$ flatpak search inkscape
$ flatpak install flathub org.inkscape.Inkscape
$ flatpak update

Installing as your user keeps the app in your own data; sudo flatpak install --system makes it available to every account on the machine. Either way it lands on the writable data partition, not in the system image.

What is already installed

Firefox ships with the image so the machine is useful the moment it boots. Everything else — office suites, editors, media players, chat, games, developer tools — is a search away in Discover.

Sandboxing, briefly

Flatpak applications run with limited access to your system and ask for more through portals: the file picker you see when an app opens a file is the system’s, not the app’s, and the app only receives the file you chose. This is why Flatpak apps cannot quietly rummage through your home folder.

If an app needs broader access — a backup tool, say — you can grant it in Discover’s permissions page for that app, or with flatpak override.

When there is no Flatpak

Three options, in the order worth trying them:

1. Check Flathub again under a different name. Coverage is broad and improving.
2. Run it in a container. Distrobox is built in (new in 0.3.0), and a container gives you a full conventional distribution to install into without touching the host — see developer tools.
3. Run it from your home folder. AppImages and self-contained binaries work normally.

What you cannot do is install it into the system image — see what immutable means.

Removing things

$ flatpak uninstall org.inkscape.Inkscape
$ flatpak uninstall --unused

The second command clears out runtimes nothing needs any more, which is where most of the reclaimable space usually is.