When it comes to cyber security, Edward Snowden is about as focused on the subject as anyone on the planet. You may not care for his actions, but when he chooses a secure communication app to use for himself, you can bet that it's about as good as it gets. The app he uses is called Signal and it doesn't require you to be a tech expert to use it. Unlike other messaging apps, you aren't required to 'sign up' in order to use it. It makes use of what you already use every day, like your phone number and local contacts without tracking what you're doing. It uses very elaborate encryption technology to make sure only those that are meant to see a message are the ones that can see them. You can make it your default messaging tool because it automatically determines who's using it on the other end or not. For those looking for the most secure messaging available, look no further than https://signal.org