12 Signal App Tips for Secure Chats

You can make both voice and video calls on Signal.

One-on-One Calls
For mobile, select the pencil icon and then choose a contact or enter a phone number. On a desktop, enter the number into search or just select a contact. Select the phone icon for a voice call or the video camera icon for a video call. On video calls, you can hide yourself by tapping the video camera icon.

Group Calls
For a group video call of up to eight people, open a group chat with the participants and select the video camera icon.

To ensure you have secure communication with a contact, you can verify safety numbers with them either in person or through messages. To do this, open a conversation in Signal, tap the other person's name up top, and select View Safety Number. This will bring up a QR code and strings of numbers. If you are physically with the other person, hover your phone over theirs and select Scan Code at the bottom of the screen.

But what if your safety number changes after getting a new phone or re-installing Signal? Don't worry, Signal verifies safety numbers inside a message. When a message comes in from a user you've communicated with but who has a new safety message, you'll see a notification within the message screen (though you can still proceed with the conversation). Tap the message that says Safety number changed. Tap to verify. Then you can either accept the new safety number in a pop-up right there or click Accept New Safety Number and be led through the manual process again.

Read receipts are a blessing and a curse. If you want them for Signal, go to Settings > Privacy > Read Receipts and toggle it to on. The feature requires mutual trust, though; both users need to enable it to see the other's receipts.

Since Signal is secure, clearing your history isn't a necessity, but if you like the neatness of no messages, want a clean start, or are worried about your phone in someone else's hands, go to Settings > Privacy > Clear History > Delete Everything.

Signal warns that the disappearing messages feature "is not for situations where your contact is your adversary—after all, if someone who receives a disappearing message really wants a record of it, they can always use another camera to take a photo of the screen before the message disappears." That said, if you do want to utilize them, on Android devices, go to a chat and tap on the timer icon. There you can select Disappearing Messages and set a time for how long they can be seen. On iOS, tap the contact or group name and then in chat settings select Disappearing Messages and set a time limit. On the desktop, go into a chat, select More and then Disappearing Messages to set a time limit.

If you're using Signal on a computer, there are lots of keyboard shortcuts, all shown on this handy chart. It's made for Mac users but for Windows or Linux, just substitute Control for Command.

Signal is a serious platform, but not too serious since it embraces things like stickers. When you go to message a contact, tap the sticky note symbol on the chat box, where you can access sticker packs like Zozo the French Bulldog.

GIFs are a tap away in Signal. In a chat, tap the plus sign next to the message box and then the GIF button to search Giphy for the perfect meme.

If you get a call from someone who's not in your contacts, you'll first see their profile picture and get a text message request to approve or block them.

You can move your Signal account from one iOS device to another easily if you have both devices on you and Signal is already installed on one. On the new device, download Signal and start registration. Once you verify your phone number, you'll get a prompt on the old device asking you whether you want to transfer your account. Once you confirm you'll get a QR code on the new device. Scan it with the old device and all your info will be moved over.

For all the ways it addresses privacy, Signal does not give you a way to mask your phone number, oddly. There is no simple solution, but there are things you can do.

As the The Intercept outlines, you can register using a number from a service such as Google Voice or Skype and tie that number to a dedicated device. That second part is easy for Android users because you can set up a second account on your phone. On iPhone, you'll have to either use another iOS device (like an iPad or an iPod touch) or Android device, but that gadget does not need a cellular connection or SIM card.

On the additional device or from the alternate account, install Signal, open it, and type in the phone number you wish to use. You will get a message that authentication failed. Choose voice verification by tapping Call Me. The number you entered will ring and you will hear a voice that will give you a six-digit number. Type that number into the verification box in the Signal app and then select Verify.

This is a messy process, but if keeping your private number private is important to you, it could be worth it.

There are lots of reasons why you wouldn't want to show faces in a photo, and last year showed that one of them is because it enables law enforcement to make arrests based on images from protests. When you go to send an image, there are tools displayed at the top. Tap the circle on the left and you'll be able to smudge out faces or other things from the photo, though this is far from a foolproof method of obscuring an identity.

Not ready to give up WhatsApp? Check out our tips for the Facebook-owned chat app.