CoCrypt

From the App Store Source

CoCrypt protects your files with collective encryption — a file can only be unlocked when every trusted participant is physically present and confirms in person. No exceptions. How It Works 1. Key Registration: Each participant generates a unique cryptographic key pair on their own device. Public keys are exchanged wirelessly through physical proximity — nothing leaves the room. 2. Locking: The owner encrypts any file. The encryption key is mathematically split into fragments, one per participant, and sealed into a single .cvl file. 3. Collective Unlocking: Every participant must physically bring their device close to unlock. A single missing presence makes decryption mathematically impossible — forever. Key Features - N-of-N Collective Approval: Ownership is truly shared. Not one person, not a majority — everyone must be present. - Presence-Based Key Exchange: Keys are exchanged through physical proximity only. No internet, no cloud, no remote access. - Challenge-Response Protocol: Every session uses a unique time-stamped ECDSA challenge, making replay attacks impossible. - Zero-Cloud & Zero-Account: No servers. No accounts. No telemetry. Private keys never leave the device's secure hardware. - Universal File Support: Documents, photos, videos, archives — any file format can be locked. Ideal For - Enterprises: Require all board members to be physically present before accessing critical files. - Families: Protect inheritance documents, accessible only when the whole family is together. - Teams: Store shared secrets where no single individual holds complete authority. - Journalists: Tie source access to the physical authorization of multiple colleagues.

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