Hello, my name is Chloe and I want to talk about how to keep your comms private and protected.
To start, here's a simple breakdown of secure messaging options, and notable risk factors:
| Platform | Encryption Type | Open Source | Ease of Use | Device Compatibility | F-Droid/APK | Self Host? | Federated* | Risk Factors | Recommendation? |
|---|---|---|---|---|---|---|---|---|---|
| Signal | E2E | Yes | High | Excellent | Yes | No | No | Phone number required, US company | Primary |
| Matrix | E2E | Yes | Medium | Good | Yes | Yes | Yes | Metadata visible to servers, UK foundation | Secondary, Primary |
| Telegram | Transport + Optional E2E | Partially | High | Excellent | No | No | No | Not E2E by default, Russian company | Use with caution |
| Session | E2E (TOR) | Yes | Medium | Good | F-Droid with own repo | No | No | Smaller user base, uses TOR which is trivially detectable. Swiss company (this is a plus) | Secondary, with increased adoption may become more practical. |
| E2E* | NO | High | Good | No | No | No | Owned by Meta, potentially backdoored. US based. | Do Not Use | |
| Briar | E2E | Yes | Low | Android only | Yes | Yes(N/A) | P2P | Complex setup, limited platforms. US based(?) but not really relevant as no servers at all. | Secondary |
First, the one you've probably heard of: Signal. Signal is an E2E (End to End) encrypted messaging platform, built by the Signal Foundation. It's open source, easy to install, available on just about every platform, and secure. However, there are some (significant) drawbacks for some use cases. The number one issue: Phone number requirement. To use Signal, you are required to A. Have a phone number and B. Start the sign up/account creation process on a phone.
Second, Matrix. Technically, Matrix is the server + protocol used on the backend, with various different apps as a front end. The most notable of these is Element (link to my instance, email or Signal for registration code), which has a few different "flavors" of its own. Matrix is unique among the rest of these options as it is decentralized, open source, and self hostable. Note that one of the risk factors is that metadata is available on the server side (i.e. who you talk to, how often, etc), but this can be mitigated to some extent by self hosting and utilizing only your own server for communication with a secure group. If the server you use as your primary becomes backdoored, seized, or otherwise compromised, the same risks still apply.
Third: Telegram. Telegram is a messaging app that relies on a central messaging server (as opposed to Signal, where all messages are stored on device(s) you are logged in to). In some cases (Secret Chats), the messages are only stored on device, similar to signal, but as mentioned above, Telegram does NOT use E2E encryption by default. This means that you can create private chats and messaging, you have the possibility that you forget to use an encrypted chat, or, with the central messaging server, that your messages are accessible to the server. Additionally, Telegram runs their own encryption for E2E, as opposed to other more vetted options.
Fourth: Session. Session is a relatively new messaging app that focuses on privacy and anonymity. It is built on the Oxen blockchain and uses a unique onion routing protocol to obfuscate user metadata. This means that not only are messages end-to-end encrypted, but the metadata (who you talk to, when, etc.) is also hidden. At this time, adoption is small, and requires more configuration than something like Signal.
Fifth: WhatsApp. WhatsApp is a widely used messaging app that offers end-to-end encryption by default. However, it is owned by Facebook, which raises concerns about data privacy and potential backdoors. Facebook/Meta have frequently cooperated with governments and authorities, and it should be assumed that if asked, they would continue to do the same.
Finally, Briar. Briar is a unique messaging app that is designed for peer to peer communication. It can work over Bluetooth, standard internet, or Tor. It uses a peer-to-peer network to send messages directly between devices, without relying on a central server. This makes it highly resilient and private, but also means that it may not be suitable for all use cases. The biggest drawback is that participants are required to be online at the same time to communicate, and if not, requires the use of a Briar Mailbox, a dedicated, always on Android device that serves as storage location for messages until your device comes back online. As of now, Mailbox only runs on Android. Briar itself can run on desktop or Android.