Linux Mint doesn’t include Canonical’s Snap system by default. Adding it requires a bit of editing at the command line, and there are online guides for that. Other than that, Flatpak is available from the get-go. Software Manager is a Gnome-style app installation front-end. It’s very well populated with packages and includes ratings and reviews.
Lubuntu does have Snap installed, but doesn’t come with Flatpak. Installing Flatpak isn’t completely straightforward, because a working repository has to be specified after the actual installation. Again, there are guides for doing this online. For application installation, Lubuntu uses a highly attractive Qt-based front-end called Discover. This has a lot of content and features ratings and reviews.
Elementary OS comes with Flatpak rather than Snap, but installing Snap is a single APT command. The app store looks like some of the others, but it doesn’t include ratings and reviews, and only offers Flatpak versions rather than those from other sources, such as APT and Snap. To top it off, the UI was rather slow on our test setup, meaning that although it’s a customised solution, it’s a bit of a let-down.
Bodhi Linux has an application store, but it’s actually a website. You search the site for the desired application and then click on a link to install. It’s a bit of a limited system, although it is good to see Synaptic installed as an APT front-end. There is no built-in support for Snap or Flatpak, but they can both be added.
Zorin has Snap and Flatpak installed from the start, and the software installation front-end can draw from Snap, Flatpak and APT. Frustratingly, it lacks reviews and ratings.