Frequently Asked Questions

SimpleX uses pairwise per-queue identifiers instead of user profiles. For each connection between two users, unique identifiers are created, making it impossible to link conversations across different contacts. This approach prevents metadata analysis of your communication patterns.

Signal uses phone numbers to identify users and their contacts, exposing metadata about who you communicate with. SimpleX protects both your message content and your network metadata completely by using no persistent user identifiers at all.

Since you have no identifier on the SimpleX platform, you cannot be contacted unless you share a one-time invitation link or an optional temporary user address. This prevents unsolicited contact and spam messages.

SimpleX uses multiple layers of encryption:

• NaCl cryptobox for per-queue encryption
• Double ratchet algorithm for end-to-end encryption in conversations
• Post-quantum resistant key exchange in every ratchet step
• Additional encryption layer for messages delivered from server to recipient

SimpleX offers multiple layers of IP protection:

• Private message routing by default to hide your IP from unknown relays
• Support for accessing servers via Tor for enhanced anonymity
• Confirmation prompts before downloading files from unknown servers
• Transport isolation using different TCP connections and Tor circuits

All user data is stored on client devices only. Messages are only held temporarily on SimpleX relay servers until they are received. Your contacts, groups, and all messages are stored encrypted locally with a passphrase. You have complete ownership and control of your data.

Connecting is simple:

1. Share a one-time connection link with your friend via any channel (SMS, email, in-person)
2. Your friend opens the link in SimpleX Chat
3. The connection is established
4. Verify the connection security code to ensure you're talking to the right person

The channel you use to share the link doesn't need to be secure since the connection itself is private.

SimpleX is available on:

• iOS - App Store and TestFlight
• Android - Google Play, F-Droid, and direct APK download
• Desktop - Terminal CLI for Linux, macOS, and Windows

All platforms offer the same features and end-to-end encryption.

Yes! SimpleX is designed for user-owned networks. You can run your own SimpleX servers and still communicate with people using pre-configured servers or any other SimpleX servers. This gives you complete control over your infrastructure while maintaining interoperability.

SimpleX Chat is primarily written in Haskell, a purely functional programming language known for its strong type system and reliability. This choice ensures high security and correctness in the implementation.

There are many ways to contribute:

• Code contributions - help develop features or fix bugs
• Documentation - write tutorials and guides
• Translation - help translate SimpleX to more languages
• Security research - report vulnerabilities
• Donations - support the development financially

Join our developer community on SimpleX to get started.

Yes, SimpleX Chat is fully open source and licensed under the GNU Affero General Public License v3.0. All protocols and implementations are public domain, ensuring transparency and allowing anyone to build upon the technology.

While these platforms don't require real identities, they still use persistent anonymous identifiers. This creates risks where connection graphs can be analyzed, potentially de-anonymizing users. SimpleX is unique in having no identifiers at all, making it impossible to link conversations across different contacts.

SimpleX offers superior privacy and security compared to WhatsApp and Telegram, which both collect metadata about your contacts and communication patterns. While it may not have all the features of mainstream apps yet, it provides the most private messaging experience available today.