Introducing
PostNumber
PostNumber is your secure, unique digital identifier on Letro.
What is PostNumber?
End-to-end (E2E) communication is at the core of Letro’s approach. It ensures that only the sender and intended recipient(s) can access the content of messages or shared data. No third parties—including service providers—can intercept or decrypt this information.
Why PostNumber Matters
Decentralized Freedom
PostNumber operates without third-party control, giving you full ownership of your communication
Portable Identity
Easily transfer your PostNumber across apps or institutions, keeping your identity intact.
Built-In Privacy
Block spam and impersonation, PostNumber protects your identity from the start.
Sealed Security
Send encrypted messages and documents, accessible only by the recipient.
How It Works with Digital Identity
Letro’s PostNumber is created by scanning a biometric passport via NFC, generating a zero-knowledge proof of identity traits.
Users register by scanning their biometric passport via NFC.
Letro creates a zero-knowledge proof of selected identity traits.
A unique PostNumber is issued upon successful registration.
All without storing sensitive data – only proofs are retained.
Institutional & Government Use Cases
PostNumber empowers institutions to issue secure, ZK-verifiable digital IDs, replacing outdated systems. It ensures tamper-proof communication, streamlined onboarding, access control, and document flow using a single identifier.
Official PostNumber Issuance
Issue secure PostNumbers to citizens, employees, or members for trusted digital identities.
Modernized Identity Systems
Replace outdated ID systems with ZK-verifiable identities anchored by PostNumber.
Tamper-Proof Communication
Ensure all internal and external communications are secure, verifiable, and tamper-proof.
Streamlined Operations
Enable seamless onboarding, access control, and document flow with a single PostNumber.
Register Your PostNumber
Download the application and start an end-to-end secure conversation.
