What is the relation between pacman and the "software" app?

I just got a new pinephone with manjaro. I didn’t found a package for chinese fonts in the software app so i logged in with ssh and installed it. So my question is what is the software app exactly. It doesn’t really mirror the packages available for the phone.

I’m new to manjaro and the PinePhone and also curious about this.

It seems to be the gnome software app [PKG].
When you click on “Software Repositories” in the top right menu it shows [core] and [extra] and one that is out of view (I guess [community]).

I assume it takes everything from these repos and only lists all apps that would install an appdata.xml file into /usr/share/appdata/%{id}.appdata.xml