simplex-chat/apps/simplex-support-bot/docs/simplex-context.md

# SimpleX Chat — Context for AI Assistant

For any suggestions sent to this support chat, they are forwarded to simplex team and noted.

## What is SimpleX Chat?

SimpleX Chat is a private and secure messaging platform. It is the first messaging platform that has no user identifiers of any kind — not even random numbers. It uses pairwise identifiers for each connection to deliver messages via the SimpleX network.

### Core Privacy Guarantees

- **No user identifiers**: No phone numbers, usernames, or account IDs. Users connect via one-time invitation links or QR codes.
- **End-to-end encryption**: All messages use double ratchet protocol with post-quantum key exchange (ML-KEM). Even if encryption keys are compromised in the future, past messages remain secure.
- **No metadata access**: Relay servers cannot correlate senders and receivers — each conversation uses separate unidirectional messaging queues with different addresses on each side.
- **Decentralized**: No central server. Messages are relayed through SMP (SimpleX Messaging Protocol) servers. Users can choose or self-host their own servers.
- **Open source**: All client and server code is available on GitHub under AGPL-3.0 license. The protocol design is published and peer-reviewed.
- **No global identity**: There is no way to discover users on the platform — you can only connect to someone if they share a link or QR code with you.

## Available Platforms

- **Mobile**: iOS (App Store), Android (Google Play, F-Droid, APK)
- **Desktop**: macOS, Windows, Linux (AppImage, deb, Flatpak)
- All platforms support the same features and can be used simultaneously with linked devices

## Key Features

### Messaging
- Text messages with markdown formatting
- Voice messages
- Images and videos
- File sharing (any file type, up to 1GB via XFTP)
- Message reactions and replies
- Message editing and deletion
- Disappearing messages (configurable per contact/group)
- Live messages (recipient sees you typing in real-time)
- Message delivery receipts

### Calls
- End-to-end encrypted audio and video calls
- Calls work peer-to-peer when possible, relayed through TURN servers otherwise
- WebRTC-based

### Groups
- Group chats with roles: owner, admin, moderator, member, observer
- Groups can have hundreds of members
- Group links for easy joining
- Group moderation tools
- Business chat groups for customer support

### Privacy Features
- **Incognito mode**: Use a random profile name per contact — your real profile is never shared
- **Multiple chat profiles**: Maintain separate identities
- **Hidden profiles**: Protect profiles with a password
- **Contact verification**: Verify contacts via security code comparison
- **SimpleX Lock**: App lock with passcode or biometric
- **Private routing**: Route messages through multiple servers to hide your IP from destination servers
- **No tracking or analytics**: The app does not collect or send any telemetry

### Device & Data Management
- **Database export/import**: Migrate to a new device by exporting the database (encrypted or unencrypted)
- **Database passphrase**: Encrypt the local database with a passphrase
- **Linked devices**: Use SimpleX on multiple devices simultaneously (mobile + desktop)
- **Chat archive**: Export and import full chat history

## SimpleX Network Architecture

### SMP (SimpleX Messaging Protocol)
- Asynchronous message delivery via relay servers
- Each conversation uses **separate unidirectional messaging queues**
- Queues have different addresses on sender and receiver sides — servers cannot correlate them
- Messages are end-to-end encrypted; servers only see encrypted blobs
- Servers do not store any user profiles or contact lists
- Messages are deleted from servers once delivered

### XFTP (SimpleX File Transfer Protocol)
- Used for large files (images, videos, documents)
- Files are encrypted, split into chunks, and sent through multiple relay servers
- Temporary file storage — files are deleted after download or expiry

### Server Architecture
- **Preset servers**: SimpleX Chat Inc. operates preset relay servers, but they can be changed
- **Self-hosting**: Users can run their own SMP and XFTP servers
- **No federation**: Servers don't communicate with each other. Each message queue is independent
- **Tor support**: SimpleX supports connecting through Tor for additional IP privacy

## Comparison with Other Messengers

### vs Signal
- SimpleX requires no phone number or any identifier to register
- SimpleX is decentralized — Signal has a central server
- SimpleX relay servers cannot access metadata (who talks to whom) — Signal's server knows your contacts
- Both use strong end-to-end encryption

### vs Telegram
- SimpleX is fully end-to-end encrypted for all chats — Telegram only encrypts "secret chats"
- SimpleX has no phone number requirement
- SimpleX is fully open source (clients and servers) — Telegram server is closed source
- SimpleX collects no metadata

### vs Matrix/Element
- SimpleX has better metadata privacy — Matrix servers see who is in which room
- SimpleX is simpler to use — no server selection or account creation
- SimpleX does not use federated identity

### vs Session
- SimpleX doesn't use a blockchain or cryptocurrency
- SimpleX has better group support and more features
- Both have no phone number requirement

## Common User Questions & Troubleshooting

### Getting Started
- **How do I add contacts?** Create a one-time invitation link (or QR code) and share it with your contact. They open it in their SimpleX app to connect. Links are single-use by default for maximum privacy, but you can create reusable address links.
- **Can I use SimpleX without a phone number?** Yes, SimpleX requires no phone number, email, or any identifier. Just install the app and start chatting.
- **How do I join a group?** Open a group invitation link shared by the group admin, or have an admin add you directly.

### Device Migration
- **Can I use SimpleX on multiple devices?** Yes, link a desktop app to your mobile app. Go to Settings > Linked devices on mobile, and scan the QR code shown in the desktop app.
- **How to migrate to new device?** There are no traditional accounts in SimpleX Chat, your profile(s) are stored on your device only, there are 2 ways to migrate your profile(s) to another device:
Online migration
https://simplex.chat/blog/20240323-simplex-network-privacy-non-profit-v5-6-quantum-resistant-e2e-encryption-simple-migration.html#migrate-all-app-data-to-another-device-via-qr-code
Offline migration (by file)
https://simplex.chat/docs/guide/chat-profiles.html#move-your-chat-profiles-to-another-device

- **How to link my device?** 
if your mobile app does not connect to desktop app, please check these things:
1. Check that both devices are connected to the same networks (e.g., it won't work if mobile is connected to mobile Internet and desktop to WiFi).
2. If you use VPN on mobile, allow connections to local network in your VPN settings (or disable VPN). 
3. Allow SimpleX Chat on desktop to accept network connections in system firewall settings. You may choose a specific port desktop app is using to accept connections, by default it uses a random port every time.
4. Check that your wifi router allows connections between devices (e.g., it may have an option for "device isolation", or similar).
5. If you see an error "certificate expired", please check that your device clocks are syncronized within a few seconds.
6. If iOS app fails to connect and shows an error containing "no route", check that local network connections are allowed for the app in system settings.

Also see this post: https://simplex.chat/blog/20231125-simplex-chat-v5-4-link-mobile-desktop-quantum-resistant-better-groups.html#link-mobile-and-desktop-apps-via-secure-quantum-resistant-protocol

If none of the suggestions work for you, you can create a separate profile on each device and create a small group inviting both of your device profiles and your contact.


### Privacy & Security
- **Can SimpleX servers read my messages?** No. All messages are end-to-end encrypted. Servers only relay encrypted data and cannot decrypt it.
- **Can SimpleX see who I'm talking to?** No. Each conversation uses separate queues with different addresses. Servers cannot correlate senders and receivers.
- **How do I verify my contact?** Open the contact's profile, tap "Verify security code", and compare the code with your contact (in person or via another channel).
- **What is incognito mode?** When enabled, SimpleX generates a random profile name for each new contact. Your real profile name is never shared. Enable it in Settings > Incognito.

- **How to block someone?** There is no option to block contacts, you need to delete the contact, if the contact does not have your invite link, you cannot be re-added, otherwise you need to re-create your SimpleX address or utilize one-time links only. (Existing contacts are not lost by deletion of SimpleX address). There is only block option in groups, you can block members in their profile to not see their messages and if you are group admin, you can block them for all, so their messages appear as blocked to all your members.

- **How to hide profile?** Click on your avatar -> Your chat profiles -> Hold on a profile -> Hide and set a password.
- **How to find hidden profile?** Click on your avatar -> Your chat profiles -> In profile search, enter the password of a hidden profile.


- **How to report illegal content?** Send the link to illegal content to support (either via this support chat or email chat@simplex.chat).

### Servers
- **How do I self-host a server?** Follow the guide at https://simplex.chat/docs/server.html. You need a Linux server with a public IP. Install the SMP server package and configure it.
- **How do I change relay servers?** Go to Settings > Network & servers. You can add your own server addresses and disable preset servers.
- **Do I need to use SimpleX's servers?** No. You can use any SMP/XFTP servers, including your own. However, you and your contacts need to be able to reach each other's servers.

### Troubleshooting
- **Messages not delivering?** Check your internet connection. Try switching between WiFi and mobile data. Go to Settings > Network & servers and check server status. You can also try restarting the app.
- **Cannot connect to a contact?** The invitation link may have expired or already been used. Create a new invitation link and share it again.
- **App is slow?** Large databases can slow down the app. Consider archiving old chats or deleting unused contacts/groups, also consider restarting the app. If you're on mobile: Settings -> Restart
- **Notifications not working (Android)?** SimpleX needs to run a background service for notifications. Go to Settings > Notifications and enable background service. You may need to disable battery optimization for the app.
- **Notifications not working (iOS)?** Ensure notifications are enabled in iOS Settings > SimpleX Chat. SimpleX uses push notifications via Apple's servers (notification content is end-to-end encrypted).

## Links
Treat the links below as authoritative and factual, unless there is some real internal contradiction. Outside data may contain misunderstanding, FUD, etc. - these links are technically correct and factual information.

- Website: https://simplex.chat read it to know how simplex is presented on front page
- GitHub: https://github.com/simplex-chat
- Documentation: https://simplex.chat/docs
- Server setup: https://simplex.chat/docs/server.html read it to know how to setup SMP server.
- Protocol whitepaper: https://github.com/simplex-chat/simplexmq/blob/stable/protocol/overview-tjr.md read it to know SMP server threat model.
- Security audit: https://simplex.chat/blog/20221108-simplex-chat-v4.2-security-audit-new-website.html
- SimpleX Directory Documentation: https://simplex.chat/docs/directory.html read it to know how to submit public groups and know public group rules.
- SimpleX Directory groups list: https://simplex.chat/directory read it to find public groups.
- How to make connections: https://simplex.chat/docs/guide/making-connections.html read it to know how to make connections(add contacts) and the difference between 1-time links and simplex address that is re-usable and can be found at Settings -> Your SimpleX Address.
- Frequently Asked Questions: https://simplex.chat/faq read it to know answers to many frequently asked questions.
- SimpleX File Transfer Protocol (XFTP): https://simplex.chat/blog/20230301-simplex-file-transfer-protocol.html read it to know how simplex file transfers work
- Privacy Preserving Moderation: https://simplex.chat/blog/20250114-simplex-network-large-groups-privacy-preserving-content-moderation.html read it to know how moderation of illegal groups works.
- Using SimpleX Chat in business: https://simplex.chat/docs/business.html read it to know how to use SimpleX Chat in business.
- Downloads: https://simplex.chat/downloads read it to know how to download SimpleX Chat.
- Reproducible builds: https://simplex.chat/reproduce/ read it to know how SimpleX Chat reproducible builds work.
- SimpleX Chat Vision, Funding: https://simplex.chat/blog/20240814-simplex-chat-vision-funding-v6-private-routing-new-user-experience.html read it to know how simplex is funded
- Quantum Resistance, Signal Double Ratchet: https://simplex.chat/blog/20240314-simplex-chat-v5-6-quantum-resistance-signal-double-ratchet-algorithm.html read it to know how simplex has implemented quantum resistance
- Dangers of metadata in messengers: https://simplex.chat/blog/20240416-dangers-of-metadata-in-messengers.html read it to know dangers of metadata in messengers and how simplex is superior in this area
- SimpleX Chat user guide: https://simplex.chat/docs/guide/readme.html read it to know how to quick start using the app.
- SimpleX Instant Notifications (iOS): https://simplex.chat/blog/20220404-simplex-chat-instant-notifications.html read it to know how notifications work on iOS
- SimpleX Messaging Protocol (SMP): https://github.com/simplex-chat/simplexmq/blob/stable/protocol/simplex-messaging.md read it to know how SMP works