Follow up to #4 , would you be interested in a compatible tools section in the readme? If so, I could put something together.

Based on #4 I believe the following are compatible:

1. OpenPGP - gpg / pgp command line tool - well duh! 😁
2. OpenKeychain (for Android) can encrypt/decrypt files and the clipboard, as well as Share-To Intent.
3. GpgFrontend (cross platform desktop QT) from https://github.com/saturneric/GpgFrontend/
4. EncryptPad (cross platform desktop QT) from https://github.com/evpo/EncryptPad - this is similar to EncryptedNotepad2 but doesn't have mobile support
5. https://github.com/clach04/puren_tonbo - my suite of tools, the main features are grep-like tool(s) for searching encrypted files, along with some integrations with text editors (vim and scite) and Git for diff'ing encrypted files