Installing Signal on Ubuntu

1. Install the official public software signing key:

wget -O- https://updates.signal.org/desktop/apt/keys.asc | gpg --dearmor | sudo tee /usr/share/keyrings/signal-desktop-keyring.gpg > /dev/null

2. Add the Signal repository to your list of repositories:

echo 'deb [arch=amd64 signed-by=/usr/share/keyrings/signal-desktop-keyring.gpg] https://updates.signal.org/desktop/apt xenial main' | sudo tee /etc/apt/sources.list.d/signal-xenial.list

3. Update your package database and install Signal:

sudo apt update && sudo apt install signal-desktop

You can now find Signal in your applications.