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AgePony brings post-quantum, age-protocol file encryption and signing to iPhone and Android, with no accounts and no backend.

AgePony is a free, open-source app that brings the age encryption protocol to iPhone and Android. Encrypt files to an age key, an SSH key, a GitHub username, or a quantum-safe ML-KEM-768 hybrid key; sign them with an in-app key, the Secure Enclave, or a tapped FIDO security key; and verify signatures from anyone. Files of any size work, because nothing is held in memory. Everything happens on the device. There are no accounts, no tracking, and no servers.

AgePony is a free, open-source file encryption and signing app for iPhone and Android, built on the modern age protocol by NorseHorse, a solo independent developer. It does on a phone what the age and ssh-keygen command-line tools do on a desktop, while staying bit-for-bit compatible with them. You can encrypt files to an age recipient, an SSH public key, or a GitHub username, and protect a file with a passphrase when there is no recipient. Version 3.0 added post-quantum recipients: a hybrid of ML-KEM-768, the lattice scheme standardised as FIPS 203, with classical X25519, so a file recorded today stays sealed even if X25519 is broken years from now. The same release moved signing inside the ciphertext, so signing and encrypting in one step produces a single file whose signature is invisible to anyone who intercepts it. Version 3.1 removed the file size ceiling entirely by streaming every operation, so a 1 GB file encrypts, signs and decrypts using no more memory than a small one. Signatures remain standard SSHSIG, made with an in-app SSH key, a hardware Secure Enclave key, or an external FIDO security key tapped over NFC. Every file is standard age and every signature is standard SSHSIG, so nothing is locked to the app. AgePony has no accounts, no analytics, and no backend of any kind; both apps are open source under Apache-2.0. It has a sibling, PGPony, that covers the full OpenPGP world for people who need it.