Video by Lauren Feeney

Whether your private conversations are personal, professional, or political, what you say or type into your phone may be of interest to snooping governments, both foreign and domestic. Criminals might be interested as well, especially when you send someone a password or credit card number. There are others you might worry about too: You might want to apply for a job without your current employer finding out. You might discuss something with a lawyer. You might talk to your friends about attending a protest, getting an abortion, or buying a gun. You might send private selfies to your partner that you don’t want anyone else to see. You might be dating someone new and not want your coworkers to find out. The list goes on.

Fortunately, privacy is a fundamental human right.

Unfortunately, most ways that people communicate with their phones — voice calls, SMS messages, email, Facebook, Skype, Hangouts, etc. — are not as private as you might think. Your phone company, internet provider, and the corporations that make the apps you use to communicate can spy on what you say. Your chats can be accessed by police, the FBI, and spy agencies like the NSA. They can also be seen by anyone who can pick up your phone and sift through it. Some of them can even be read by anyone in a position to simply glance at your phone’s lock screen and read the notifications displayed there.

But it’s possible to make sure that your private conversations are actually private. It starts with installing an app known as Signal, and getting your friends to install it too. Then you’ll want to tweak the settings to lock everything down.

The Signal app is easy to use, works on both Apple’s mobile operating system iOS and Google’s Android, and encrypts communications so that only you and the people you’re talking to can decipher them. It also has open source code, so experts can verify its security claims. You can download Signal from the Android Play Store and the iPhone App Store.

Although Signal is well-designed, there are extra steps you must take if you want to maximize the security of your most sensitive conversations. (I outlined some of these steps last year, but Signal has changed significantly since then.) There are also some useful features in Signal that you might not know about.

I discuss these at length below — and in the video above, created with Lauren Feeney.

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