Signal vs. WhatsApp vs. Telegram: Here's which secure messaging app to use

If your choice of encrypted messaging app is a toss-up between Signal, Telegram and WhatsApp, do not waste your time with anything but Signal. This isn't about which has cuter features, more bells and whistles or is most convenient to use -- this is about pure privacy. If that's what you're after, nothing beats Signal.

By now you probably already know what happened. On Jan. 7, in a tweet heard 'round the world, tech mogul Elon Musk continued his feud with Facebook by advocating people drop its WhatsApp messenger and use Signal. Twitter CEO Jack Dorsey retweeted his call. Around the same time, right-wing social network Parler went dark following the Capitol attacks, while political boycotters fled Facebook and Twitter. It was the perfect storm -- the number of new users on Signal and Telegram has surged by tens of millions since.

Read more: Everything to know about Signal

The jolt also reignited security and privacy scrutiny over messaging apps more widely. Among the three currently dominating download numbers, there are some commonalities. All three are mobile apps available in the Play Store and App Store, and which support cross-platform messaging, have group chat features, offer multifactor authentication, and can be used to share files and photos. They all provide encryption for texting, voice and video calls.

Signal, Telegram and WhatsApp all use end-to-end encryption in some portion of their app, meaning that if an outside party intercepts your texts, they should be scrambled and unreadable. It also means that the exact content of your messages supposedly can't be viewed by the people working for any of those apps when you are communicating with another private user. This prevents law enforcement, your mobile carrier and other snooping entities from being able to read the contents of your messages, even when they intercept them (which happens more often than you might think).

The privacy and security differences between Signal, Telegram and WhatsApp couldn't be bigger, though. Here's what you need to know about each of them.