Quldra

Quldra is a messaging app built from the ground up for post-quantum security. Every conversation is protected by ML-KEM-768 key exchange and ChaCha20-Poly1305 authenticated encryption -- not as an optional upgrade, but as the foundation of every session.

BUILT FOR WHAT COMES NEXT

Classical encryption will not survive the arrival of large-scale quantum computers. Quldra addresses this directly. Session keys are established using ML-KEM-768 (FIPS 203), with a KEM-based ratchet that generates fresh keying material on every direction change. Signatures use an Ed25519 + ML-DSA-65 hybrid scheme, providing both classical and post-quantum authentication.

The result: forward secrecy, post-compromise security, and quantum-resistant confidentiality on every message you send.

ON-DEVICE CRYPTOGRAPHY

All encryption and decryption happens on your device. Private keys are stored in platform-secure storage (Keychain on iOS) and never transmitted to any server. The server stores only encrypted payloads. If compromised, it reveals nothing readable.

PRIVATE MESSAGING, YOUR WAY

Direct messages and group conversations with flexible roles (creator, admin, member). Share images, GIFs, videos, and files. Set message tones -- Work, Fun, High Priority, Personal -- to give your messages context at a glance. Reply in threads, edit or delete your own messages, and see read receipts when they matter.

Invite others with shareable links, protected by optional passwords and join-approval workflows.

PRIVACY CONTROLS THAT STAY OUT OF YOUR WAY

Lock the app with a passcode or biometrics. Hide message previews from your lock screen. Create hidden rooms for conversations you want to keep separate. Configure push notifications down to whether sender names appear.

ACCOUNT RECOVERY WITHOUT A PHONE NUMBER

Quldra does not require a phone number. Your account is secured by a 12-word seed phrase generated at signup. Store it safely -- it is the only way to recover your install on a new device.

BANDWIDTH-BASED PRICING

Quldra charges for data transferred. Every install starts with a free tier. When you need more, choose what fits:

• Starter Monthly: 1 GB of messaging bandwidth for $2.99/month
• Top-Up: $4.99 per GB, use it at your own pace with no expiration

No ads. No data mining. You pay for infrastructure, nothing else.

Terms of Use: https://quldra.com/terms.html
Privacy Policy: https://quldra.com/privacy.html