The first messenger
without user IDs
Other apps have user IDs: Signal, Matrix, Session, Briar, Jami, Cwtch, etc.
SimpleX does not, not even random numbers.
This radically improves your privacy.
Make a private connection
The video shows how you connect to your friend via their 1-time QR-code, in person or via a video link. You can also connect by sharing an invitation link.
Why privacy matters
Preserving the privacy of your metadata — who you talk with — protects you from:
Advertising and price discriminationPrivacy saves you money
Manipulation of electionsPrivacy gives you power
Prosecution due to innocent associationPrivacy protects your freedom
Make sure your messenger can't access your data!
Why SimpleX is unique
E2E-encrypted messages with markdown and editing
images and files
Decentralized secret groups —
only users know they exist
E2E-encrypted voice messages (coming soon)
Disappearing secret conversations (coming soon)
audio and video calls
Portable encrypted database — move your profile to another device
Incognito mode —
unique to SimpleX Chat
What makes SimpleX private
Simplex Chat provides the best privacy by combining the advantages of P2P and federated networks.
Unlike P2P networks
All messages are sent via the servers, both providing better metadata privacy and reliable asynchronous message delivery, while avoiding many problems of P2P networks.
Unlike federated networks
SimpleX relay servers do NOT store user profiles, contacts and delivered messages, do NOT connect to each other, and there is NO servers directory.
servers provide unidirectional queues to connect the users, but they have no visibility of the network connection graph — only the users do.
You can create contacts and groups, and have two-way conversations, as in any other messenger.
How can it work with unidirectional queues and without user profile identifiers?
For each connection you use two separate messaging queues to send and receive messages via different servers.
Servers only pass messages one way, without having the full picture of user's conversation or connections.
The servers have separate anonymous credentials for each queue, and do not know which users they belong to.
Users can further improve metadata privacy by using Tor to access servers, preventing corellation by IP address.
Comparison with other protocols
|Signal, big platforms||XMPP, Matrix||P2P protocols|
|Requires global identity||No - private||Yes 1||Yes 2||Yes 3|
|Possibility of MITM||No - secure||Yes 4||Yes||Yes|
|Dependence on DNS||No - resilient||Yes||Yes||No|
|Single or centralized network||No - decentralized||Yes||No - federated 5||Yes 6|
|Central component or other network-wide attack||No - resilient||Yes||Yes 2||Yes 7|