How to Install Signal

Get your learners started with using the messaging app Signal. We’ll start with a short discussion of why and how someone might want to protect their communications, and then move into the specifics of installing and using Signal.

Recommended Reading

• How to: Use Signal on iOS   
• How to: Use Signal on Android   
• Different Types of Encryption   
• SSD Glossary
• Signal support center

Gotchas and Problems You Might Hit

• Sometimes it takes time for a new contact to display in someone’s Signal contact list, or they will have to refresh their list of Signal contacts. Keep this in mind during your training. Consider having participants exchange numbers with their partners earlier in the training.   
• As with other tool installations, you may encounter connectivity issues. Consider setting up your own wireless system for others to tether to your device, in case the connection fails.   
• Some participants may not feel comfortable sharing their phone number with others during this training, or may not feel comfortable using their personal phone number for Signal. The following articles can help you prepare for this kind of situation:    

  • How to Use Signal Without Giving Out Your Phone Number by Jillian York

  • Using Signal Without Giving Your Phone Number by Martin Shelton

  • How to Use Signal Without Giving Your Phone Number by Micah Lee

• Signal protects your communications, but will not protect against others reading your texts or malware retrieving your messages.  It’s important to point out that Signal is not a panacea against all threats.

• Sometimes people will not have enough storage space left to install Signal.  You may want to have people think about which apps are unnecessary before coming to the session.

Anticipated Questions and Answers

Q: What if I’m uncomfortable granting Signal access to my contacts?

A: Signal uses a cool technique called “private contact discovery” to make it possible for you to determine whether the contacts in your address book are Signal users without revealing your contacts to the Signal service. The details get a bit nitty-gritty, but people who’d like to learn more can check out Signal’s blog post about the technique.

Q: If Signal is so secure, why does it log all my messages?

A: Signal has a feature called “disappearing messages,” which ensures that messages will be removed from your device and the device of your contact some chosen amount of time after they are seen. To enable "disappearing messages" for a conversation, open the screen where you are able to message your contact. From this screen, tap the name of the contact at the top of the screen, then tap the slider next to "Disappearing Messages."

Q: What about WhatsApp? All my friends use it.

A: We don’t currently recommend WhatsApp for secure communications, but understand quite a lot of people use the app—especially internationally. Check out our WhatsApp guides for Android and iOS.

Q: Will I be targeted if someone knows I have an end-to-end encryption application installed on my phone?

A: In some countries, using Signal or other end-to-end encrypted messengers can indeed be a red flag to law enforcement, government authorities, or others monitoring at a network level. If this is a concern for you, then Signal might not be the right choice.

Q: How do I get my friends to use this app? None of them seem concerned with protecting their communications—they say they have nothing to hide.

A: Some ideas include asking if you can install the app for your friends, telling them that Signal is the best (or only!) way to contact you, and mentioning that Signal is free and works internationally.