GnuPG allows to encrypt and sign your data and communication, features a versatile key management system as well as access modules for all kinds of public key directories. GnuPG, also known as GPG, is a command line tool with features for easy integration with other applications.
- - GnuPG is the most popular Mac & Linux alternative to APG.
- - GnuPG is the most popular Open Source & free alternative to APG.
OpenKeychain helps you communicate more privately and securely. It uses high-quality modern encryption to ensure that your messages can be read only by the people you send them to, others can send you messages that only you can read, and these messages can be digitally signed so...
- - OpenKeychain is the most popular Android & Android Tablet alternative to APG.
- - Enigmail is the most popular Windows alternative to APG.
- - GPGMail is the most popular commercial alternative to APG.
WebPG is a free, open source suite of tools to bring OpenPGP (GnuPG/PGP, gpg, gnupg) to the browser, in an effort to make cryptographic methods usable, safe and accessible to the common man.Discontinued
Not maintained anymore.
OneTime is an open source encryption program that uses the one-time pad algorithm to allow two parties to communicate privately. It has features to assist with the bureaucracy of pad management, and comes with built-in help. OneTime requires Python 2.
Autocrypt is a set of guidelines for developers to achieve convenient end-to-end-encryption of e-mails. It specifies how e-mail programs negotiate encryption capabilities using regular e-mails.
- - Autocrypt is the most popular Self-Hosted alternative to APG.
CipherMail for Android is an Android application which can be used with your existing Android mail application to send and receive S/MIME digitally signed and encrypted email with an Android smartphone.