Crisix is a serverless P2P messenger with automatic transport fallback. When the internet goes down, Crisix seamlessly switches to Bluetooth, Wi-Fi Direct, DNS tunnel, or LoRa – no central servers, no SIM card, no internet required.
Crisix combines cutting-edge P2P technology with a simple, intuitive interface – built for real crisis situations.
Automatic selection of the best available transport path – from Bluetooth to DNS tunnel. If one transport fails, the next one seamlessly takes over.
ActiveDouble Ratchet + X3DH protocol with AES-256-GCM and Perfect Forward Secrecy. Your messages stay private – on every transport path.
ActiveNo central server. Peers discover each other via Kademlia DHT (BEP 5) and mDNS. NAT traversal and hole punching for direct connections.
ActiveWritten in Kotlin with Jetpack Compose & Material 3. Chat overview, contact management, QR scanner, and connection status dashboard.
ActiveAutomatically switches to the fastest available transport. From BLE to WiFi to Internet – without you having to do anything.
ActiveEach device has its own cryptographic key pair. Your identity is your fingerprint – verifiable via QR code or NFC.
ActiveCrisix prioritizes transport paths by independence – from fast and local to creative and long-range.
Three steps – and you can communicate with others, completely server-free.
Download the APK and install it on your Android device. No registration, no phone number, no email address required.
On first launch, an Ed25519 cryptographic key pair is generated. Share your QR code with others – so they can find you.
Crisix automatically selects the best available transport path. Whether internet, Bluetooth, or DNS tunnel – your message gets through. Encrypted.
Crisix is built on the privacy-by-design principle. No metadata collection, no central servers, full control.
Double Ratchet + X3DH handshake with AES-256-GCM. Each message is encrypted with a temporary session key – Perfect Forward Secrecy.
Each device has a unique cryptographic key pair. The peer ID is the SHA-256 fingerprint of the public key – unforgeable.
The private key is securely stored in the Android KeyStore. Not exportable, not readable – even if the device is compromised.
Crisix collects no metadata. No phone number, no email, no location data. Only the message and the encrypted content matter.
Crisix is free, open source, and free of tracking. Sign up and we'll notify you as soon as Crisix is available.