SimpleX Chat
The developers of SimpleX Chat are absolute legends! Clearly they’d thought outside the box when designing a messaging platform that combines End-to-End encryption, onion routing and distributed message queues. What makes SimpleX stand out is that the client applications are immediately usable, without any configuration. In fact, it’s even easier to use than WhatsApp.
SimpleX has been around for a couple of years, but I’d only recently learned of it from someone who was also frustrated with the absence of messaging platforms that allow for anonymous communication. WhatsApp, Signal and Telegram are objectively unsuitable for private and anonymous messaging, because they can’t be used without providing a cellphone number. The last thing an activist or journalist wants is a messaging app that would disclose the identities of everyone s/he was in communication with, to an adversary that gained access to the device.
Anyone can use SimpleX without providing any identifying information. In fact, there are no user accounts in SimpleX. Instead there are ‘profiles’, which are simply aliases for the client application, and a user can have any number of them - potentially one for each group or conversation.
The main identifiers for SimpleX are message queue links. A user creates a conversation or group, and shares a link to that. Anyone with the link can send and receive messages anonymously. The important thing here is that a link can be as private or as public as we want. It could be shared between two people, it could be shared among a group of people, or it could be openly posted on Web sites to make it a public group.
Potentially an activist could have a load of like-minded people join a SimpleX group by posting its QR code somewhere public, or by letting trusted individuals scan the code from his/her device.
The message routing is also very clever. Messages are sent and received, through two-layer onion routing, to message queues. By default, the client application will use different servers for sending and receiving.
This means a person operating a SimpleX server would have access only to encrypted fragments of a conversation, and would have no way of knowing who the senders and recipients are. Users only know the profile names of the people they’re communicating with. We also can’t easily determine who operates the servers.
For more paranoid security, there is the option of using Orbit (or whichever Tor client) to route SimpleX traffic over Tor.
Messages and content are only briefly stored in the message queues, and are mainly stored in an encrypted application database on the user’s device. That database can be exported, if we want to make backup copies, or migrate the application to another device.
Obviously, it’s not easy to discover groups on SimpleX yet, but it’s entirely possible that SimpleX links might become ubiquitous on the Web, and in the real world (as QR codes). Having started the labourious task of copying out directory service links to a JSON file, I’ve put together my own SimpleX Search application. I don’t have all the groups in there yet, and currently have no plans to develop that into a proper database application.
The standard method of finding public groups is subscribing to the SimpleX Directory Service, which is still rough around the edges. It took me a couple of days to get the list of ~200 existing public groups (for the JSON file). A handful of those groups are the typical cyrptocurrency grifters, but that’s to be expected with any new messaging platform. Most the other groups are for discussions about privacy and anti-censorship projects. A few are for programming-related things and current affairs.
It’s too early to predict whether SimpleX would become more popular than Signal or Telegram, but it does look promising. Most privacy-enhancing solutions fail to gain traction because they come with their learning curves and configuration requirements. SimpleX clients are immediately usable after installation, and they still have a lot of configuration options.
The biggest obstacle is the ’network effect’ - People use WhatsApp because everyone else is, but there are still numerous people who will opt for SimpleX because they need something with its security model.