Signal is a secure, free, and open source messaging application that uses end-to-end encryption to securely send and receive all kinds of communications with other Signal users. Using the Internet for all encrypted communication, Signal comes highly recommended by some of the top privacy and security advocates.
In this Signal review, we’ll look at the capabilities, usability, and security that Signal offers. We’ll also talk about how the design of the service provides extremely strong protection for your privacy. Signal is truly impressive, so let’s cut the chatter and dig in to the review.
Here are some key features to consider when deciding whether the Signal app is right for you:
- Signal is generally considered the most secure messaging app in existence.
- 100% open source code. The code is available on GitHub.
- The Signal Messaging Protocol was independently audited in 2016.
- The service is fully GDPR compliant.
- Clients for Android, iOS, Mac OS, Windows, Linux.
In 2013, Moxie Marlinspike (real name Matthew Rosenfeld) founded Open Whisper Systems to develop the Signal app and protocol. In 2018, Marlinspike and Brian Acton founded Signal Messenger, LLC, to take over the development of both the Signal app and the Signal Protocol.
Signal Messenger, LLC is funded by the Signal Technology Foundation (aka Signal Foundation), a 501(c)(3) non-profit organization. All products of the Signal Foundation are published as free and open-source software.
Where is your Signal data stored?
When you use Signal, your data is stored in encrypted form on your devices. The only information that is stored on the Signal servers for each account is the phone number you registered with, the date and time you joined the service, and the date you last logged on. As Signal points out,
Notably, things we don’t have stored include anything about a user’s contacts (such as the contacts themselves, a hash of the contacts, any other derivative contact information), anything about a user’s groups (such as how many groups a user is in, which groups a user is in, the membership lists of a user’s groups), or any records of who a user has been communicating with.
All message contents are end-to-end encrypted, so we don’t have that information either.
This is great for your privacy, since no one can get any more information than that without physical access to your device or those of the people you communicate with.
This is different from apps like Wire messenger, which stores info about your contacts on central servers. However, it does mean that if you want to keep copies of your messages, you will need to configure Signal to back them up and restore them on your device.