Universal packages are the way of the future. Don't be limited to only snaps on Ubuntu. Flatpak was developed by the Free Desktop Project and offers an outstanding alternative to snaps for the desktop. With these types of universal packages, it becomes incredibly easy to install third-party applications without having to add repositories or deal with dependencies.
But if you're wanting to make use of both Flatpak and snaps on Ubuntu, you'll have to first install Flatpak support. I'm going to show you how to get Flatpak up and running on Ubuntu. I'll be demonstrating on a daily build of Bionic Beaver desktop (Ubuntu 18.04).
The first thing we must do is add the necessary repository. To do this, open up a terminal window and issue the command:
sudo add-apt-repository ppa:alexlarsson/flatpak
You will be prompted to hit Enter on your keyboard. Do that and the repository will be added. Update apt with the command:
sudo apt update
Install flatpak with the command:
sudo apt install flatpak
We want to make this as easy as possible, so we're going to install Flatpak support for GNOME Software. To do this, open up a terminal window and issue the following commands:
sudo apt install gnome-software-plugin-flatpak flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo
Restart your system and log back in. Once the system restarts, open up your browser and point it to Flathub. Find an application you want to install, click its associated INSTALL button, and when prompted select Software Install (default) from the drop-down.
Once the installation completes, you will find the application launcher in your desktop menu. Fire up the application and enjoy.