# [SimpleX Chat](https://simplex.chat/) > [!Summary]+ Summary > SimpleX is a privacy-first messenger with **no user IDs**. Your profile, contacts, and chats live **only on your device**; messages are **temporarily queued on SimpleX relay servers** until received. It’s free/open-source and designed to minimize metadata. > ## How it connects - **Messaging path:** Not P2P. Messages use **SMP relay servers**. Since **v6.0 (2024-08-14)**, **Private Message Routing (PMR)** is **on by default**, adding a two-hop route that hides your IP/session from destination servers. - **Tor (optional):** You can route via Tor by configuring a SOCKS proxy (e.g., Orbot) and can **require `.onion` hosts** if desired. Tor is **not** used by default. - **Calls:** 1:1 audio/video uses **WebRTC**. **TURN relay is the default** for calls; you can disable it to attempt **P2P** (reveals your IP to the peer). You can also run your own **STUN/TURN**. ## Security - **E2E encryption** (Double Ratchet) with forward secrecy and break-in recovery; **quantum-resistant hybrid E2EE** is available with all contacts since **v5.7 (2024-04-26)**. - **No identifiers:** connections use per-conversation queue addresses, not usernames/phone numbers. - **Verification:** connect via one-time link/QR; optionally **verify the security code** to mitigate link-substitution attacks. ## Data & backups - **On-device first:** profile, contacts, and chats are stored locally; messages are only **held temporarily** on relays until your device receives them. - **Backups:** export/import your encrypted database from app settings. **If you lose the device without a backup, you lose the account and data.** Keep regular backups and set a database passphrase. ## Self-hosting - You can operate your own **SMP relays** and **WebRTC (STUN/TURN)** servers and still interoperate with others. ### Why I recommend it Strong metadata protections (**PMR by default**), no global identifiers, and fully local accounts with explicit, portable backups. For users who value privacy over multi-device convenience, SimpleX is a top choice.