Using Signal with Friends

In the past few days… a lot has happened. Those events have encouraged a large number of people to download Signal.

Primarily from a combination of Apple forcing apps to provide simple descriptions of their Privacy Policy and an ultimatum from Facebook to allow linking data in WhatsApp. Additionally, there are concerns¹ about changes in the white paper explaining the End-to-End encryption which protects the messages in WhatsApp².

Why Signal Link to heading

Signal is developed by the Signal Foundation a 501(3)(c) non-profit which pays the core development team. Because it is a non-profit that means they’ll have no reason to add features weakening privacy or security for profit unlike Facebook appears to have done with WhatsApp.

Additionally, their apps for iOS and Android plus the Server they run which routes your messages are open source and developed publicly on Github. There is always the risk that Signal changes their apps before releasing them to the App Store and because they are open source it’s possible to build a running copy for you self to use instead.

The design of the protocol Signal uses tries to store as little as possible on their servers and route directly to other users avoiding their server where practical. Messages are designed to be verified, private, and plausibly deniable³.

The UI of Signal is similar to WhatsApp so it’s familiar to non-technical users. A key feature of Signal is bringing safe and easy encryption to the masses and they try to make things as easy to use as possible. Performing verification of other users is also simple and can be done either in person or via some other hard-to-fake communication method where you can be sure the other person is who you think it is (like video chat)⁴.

All you need is a Phone Number (but maybe less soon) Link to heading

While Signal has been working to remove the need for a Phone number they currently still require one. Others will be notified when you join if they have your phone number in their contacts and already signed up with Signal. If it matters to you then I recommend paying for a burner phone somewhere and using that to create your account. It’s also possible to use Google Voice, Blur, or Twilio to get a virtual number too.

But that’s all you need. Besides your phone number signal will only have a copy of your Signal Contacts encrypted with the Pin you give it. This is part of the plan to allow non-phone-number accounts.

Final thoughts (Nov 2021) Link to heading

Now in November 2021 we’ve since learned that the changes to WhatsApp were much more boring UX changes being made to support businesses. Many people downloaded Signal and while some use it many continue to use WhatsApp including myself.

It’s a good thing that many were exposed to and learned about Signal because it shows people do want to have private communications.

In the end you should also download and use Signal.