Signal - privacy messanger

Install

# NOTE: These instructions only work for 64 bit Debian-based
# Linux distributions such as Ubuntu, Mint etc.

# 1. Install our official public software signing key
wget -O- https://updates.signal.org/desktop/apt/keys.asc |\
  sudo apt-key add -

# 2. Add our repository to your list of repositories
echo "deb [arch=amd64] https://updates.signal.org/desktop/apt xenial main" |\
  sudo tee -a /etc/apt/sources.list.d/signal-xenial.list

# 3. Update your package database and install signal
sudo apt update && sudo apt install signal-desktop