PGPony is an OpenPGP app for Android. Encrypt, decrypt, sign, and verify messages and files, manage your keyring, and use a hardware security key over NFC, all on device. Features: - Encrypt, decrypt, sign, and verify text and files - Post-quantum encryption: ML-KEM-768 + X25519 (Kyber) composite keys, in both the IETF draft (v6) and LibrePGP / GnuPG 2.5 (v5) formats - OpenPGP provider service: use PGPony as the crypto engine for Thunderbird for Android, K-9 Mail, and Password Store (OpenKeychain-compatible API) - Generate modern keys, including RFC 9580 (OpenPGP v6) Ed25519 and X25519, with Argon2id passphrase protection - Hardware security keys over NFC, including YubiKey 5 NFC and Token2, with on-card key generation, decrypt, sign, PIN management, and factory reset - Read your password-store (pass) entries, including those protected by a hardware key - Encrypted keyring backup and restore, including OpenKeychain backup import - PGP/MIME email: decrypt messages with attachments, compose encrypted .eml - Key discovery through WKD and the keys.openpgp.org verifying keyserver; optional Tor routing via Orbot - Optional contact integration for choosing recipients - QR import and scanning for keys - Default signing key, biometric lock, and secure-screen protection Post-quantum limitations: Post-quantum OpenPGP is still being standardized, so cross-tool support is limited: - LibrePGP-format (v5) keys interoperate with GnuPG 2.5+ today: messages encrypt and decrypt in both directions, and public keys import cleanly. GnuPG cannot yet import post-quantum PRIVATE keys from any app — it stores them in a proprietary internal format. - IETF-format (v6) keys implement draft-ietf-openpgp-pqc and are verified against the draft's official test vectors, but current Sequoia (sq) preview builds implement a different draft revision and cannot read them yet, and GnuPG does not support this format at all. - Classical keys (RSA, Ed25519, v4 and v6) are unaffected. PGPony does not us