OpenKeychain: Easy PGP

OpenKeychain keeps your messages private using OpenPGP encryption. It manages keys, encrypts/decrypts messages, and integrates with apps like K-9 Mail. Open-source and audited for security, it’s free and transparent. Supports key exchange, QR scanning, and works across devices. Learn more at http://openpgp.org/software/. Source code: https://github.com/open-keychain/open-keychain.