GNOME 3.22 Releasedhttp://www.omgubuntu.co.uk/2016/09/gnome-3-22-released-new-features
In GNOME 3.22, Software, the GNOME app store, ships with comprehensive Flatpak support.
It now lets you add Flatpak repository files, and browse/install apps from them, all without the need to consult the command line! The app also gains the ability to display further information about Flatpak apps, including source information, and sandbox status.
Damn annoying that there competing formats as Gnome and Mint 18.1 are opting for Flatpak but others like Firefox will be going for Snap.