📖Add PPAs

software-properties-common

Though in elementary OS, it is recommended to install Flatpak apps, sometimes you have to add a Personal Package Archive (PPA) to your system to get the apps you need. For example, this is the way of installing Pantheon Tweaks.

What helps you to do that is software-properties-common, which contains scripts like add-apt-repository and apt-add-repository, and thus simplifying the process of adding and removing PPAs.

Mind the recommendation from Danielle Foré (elementary OS founder):

Be aware that adding an apt repository is functionally equivalent to creating a new administrator account on your computer for the repository owner. Packages from this repository will have root permission on your computer when they are installed. So be sure you absolutely trust the repository maintainer. I highly recommend against adding third-party apt repositories to your system.

Installation of software-properties-common is simple.

Open your Terminal, and run:

sudo apt-get install software-properties-common

Now you can add PPAs to your system with the command which would look like

sudo add-apt-repository -y ppa:xxxxxxxxxx/xxxxxxxxxxx

and install the desired app from this PPA with the command like

sudo apt install <APP_NAME>

As a rule, you can always find the required installation info on the app web page (example).

Useful article about software-properties-common