Browse locally with the *Synaptic Package Manager*:

When starting Tails, [[set up an administration password|doc/first_steps/welcome_screen/administration_password]].

<p>The packages included in Tails are carefully tested for security.
Installing additional packages might break the security built into Tails. For
example, installing OpenVPN might modify the firewall rules that Tails uses to
force network traffic to go through Tor.</p>

Examples of additional useful software

Installing additional software

Installing additional software automatically when starting Tails

To install an additional package automatically when starting Tails:

Using additional software

Checking your list of additional software

To see which packages are installed automatically every time you start Tails, choose **Apps&nbsp;▸ System Tools&nbsp;▸ Additional Software**.

Removing additional software

Using *Additional Software*:

Configuring additional APT repositories (for advanced users)

<p>Configuring additional APT repositories might break the security built into
Tails and might install software that has not even been approved by Debian. Be even more careful
with what you install.</p>

Create an *apt-sources.list.d* folder in your Persistent Storage:

As root, edit */live/persistence/TailsData_unlocked/persistence.conf*, the configuration of the Persistent Storage, and add the *apt-sources.list.d* folder as a feature of type `link`:

For example, to add
the `non-free` sections of Debian 13 (Trixie), backports, and security
updates, you can create a file named
*/live/persistence/TailsData_unlocked/apt-sources.list.d/non-free.list*
with the following content:

File names must end with *.list* and must only contain the following
characters: letters, digits, underscore, hyphen, and period.

Correct the ownership and permissions of your additional `sources.list` files to be owned by `root` and only readable by others. For example, execute the following commands.