How to use the Signal app to keep your chats secure

It’s not clear whether the team at Signal believes the maxim that all press is good press, but the messaging app has very much been in the news in recent days. 

Politics and international relations aside, the incident goes to show that old-fashioned human fallibility can beat even the most secure technology. Signal is actually one of the better chat apps available, if privacy and security are your biggest priorities.

The app is available on Android, iOS, Windows, and macOS, and comes with just about all the features you could want for keeping in touch with other people: one-to-one chats, group chats, audio and video calls, file sharing, and even Snapchat-style stories. Here’s how to get started with Signal and how to make the most of the app.

Signal basics

We should start by saying Signal is end-to-end encrypted: Essentially, no one else can hack into your messages, whether that’s government agencies or Signal staff. There’s always the chance that malware on one of your devices can tap into your messaging (by monitoring keyboard input, for example), but when it comes to Signal itself, it’s locked up tight. Just be careful about who you invite into group chats.

Signal identifies you by your phone number, which you’ll need to enter when you first install the app. You’ll also be invited to create a profile on Signal so other people can see who you are—this is just your name and a photo, if you want to add one. Use the Who can find me by number? option on the profile setup page to control whether or not people who have your number can find you on Signal.

After that, it’s a question of getting your friends, family, and work colleagues to come and join you. On Android, tap the three dots (top right) then Invite friends; on iOS, tap your profile picture (top left) and Settings > Invite Your Friends. You’ll get an invite link you can then share across whatever messaging apps your contacts are using.

Assuming you’ve given the app permission to access your contacts during setup, if you tap the pencil icon (bottom right on Android, top right on iOS), you should see a list of people you know who are already using Signal—just choose a name to start chatting. In each chat, your options for sending text, images, stickers, voice notes, emojis, and your current location are all down at the bottom of the screen.

You can create a group chat by starting a chat via the pencil icon, then choosing New Group and picking your contacts. From inside a group chat, tap the name of the chat at the top to add and remove members, and set up security permissions: You can specify certain group members as admins for example (you’re automatically an admin if you created the group), and set up admin approval for new members.

The Signal interface is simple to navigate, and you’ll see three main tabs on the interface: Chats (for your messages), Calls (for audio and video calls), and Stories (for social media-style sharing). Audio and video calls are end-to-end encrypted too, and you can have up to 50 people on the same call.

Advanced Signal features

Dig deeper into Signal and you’ll find a number of advanced features available. For example, you can set messages to automatically disappear after a certain time period, once they’ve been read. This works for both one-to-one chats and group chats, and adds an extra layer of privacy and security on top of the end-to-end encryption (even if someone gets access to your phone, they can’t see deleted messages).

From inside a conversation, tap the name of the contact or the group chat at the top, then choose Disappearing Messages. There are a variety of options here, from 30 seconds to 4 weeks, and you can set a custom time if you prefer. Once everyone in a chat has seen a message, the countdown starts for its removal.

You can access plenty of other options by tapping the name of a contact or group chat at the top of a conversation pane. You can set specific colors and wallpapers for individual chats, for example, set up custom notification sounds so you can distinguish one conversation from another, or mute a conversation (very handy for those group chats that are always busy).

To get at the general settings for Signal, from the Chats tab tap the three dots (top right) then Settings on Android, or tap your profile picture (top left) and then Settings on iOS. You can change a number of options from here: Choose Appearance, for example, and you’re able to change the app theme, colors, and icon.

Also on the Settings pane you’ll find a Linked Devices setting. Choose this and follow the instructions to sync Signal messages between a phone and a desktop app on Windows or macOS—meaning you don’t have to always take your phone out to compose or reply to messages (you can take advantage of your computer’s larger keyboard too).

Other options to be aware of in Settings: Account, which lets you set up a Signal PIN for protecting unauthorized access to your account and switching between devices, and Privacy, where you can set up options such as read receipts and a screenshot blocker (so screengrabs can’t be captured on your own phone, if someone should access it).