https://delta.chat/en/
https://delta.chat/en/download
The program is available for 64-bit GNU/Linux, Android, iPhone/iPad, macOS, Windows
DeltaChat is an open source encrypted messenging app that uses your IMAP (incoming) and SMTP (outgoing) email server to communicate. It acts like an SMS messenging app but instead uses email channels to send and receive messages. It sends encrypted messages using the Autocrypt end-to-end encryption standard to other DeltaChat instances and other email capable applications that use the Autocrypt standard. https://autocrypt.org/dev-status.html
DeltaChat will also send and receive messages to regular email programs that do not use encryption, but the messages will not be encrypted when doing that.
The Debian/Ubunto .deb file installs, sends and receives messages on both BionicPup64 and FossaPup64 but does not run as root out of the box. It adds a menu entry to the "Internet" category which does not launch the app, it will launch the app after the Pet file attached to this post is installed.
The Pet is to add the switch --no-sandbox so that the menu entry will work. The tiny pet modifies the /usr/share/applications/deltachat-desktop.desktop file, so that instead of opening the DeltaChat binary it runs a start script at /opt/DeltaChat/DeltaChat -that script adds the --no-sandbox switch to the command that starts the binary deltachat-desktop --no-sandbox (the .deb file from DeltaChat did not do that, they expect normal limited user startup but at least gave root users the option to run as root)
To install in either FossaPup64 or BionicPup64, first download and install the deltachat-desktop_1.32.1_amd64.deb (from the site listed at top of this post) and then install the attached PET file. The PET file installs the two files mentioned above and then runs fixmenus in the postinst script to update the JWM Menu (added fixmenus command because the deb failed updating the menu once)
Additional info:
The app for Android smartphones is available from google and also f-droid.org (f-droid a secure app repository for non-google users that requires no login) the apple stuff is at the apple store, windows is at microsoft, etc. see the links at the top of this page for download.
This program does not require a smartphone, it can be used between computers or between smartphones and computers. It does require an email account with a server that uses IMAP and SMTP.
