@ThreeBadgersInATrenchcoat Its not based on email in that sense, you use just imap/smtp of your email provider to send encrypted messages and encryption is done by Autocrypt standard, its e2e of course. Signal is different in terms of encryption protocol (it uses famous signal protocol) and its central service, delta chat is distributed in ways that two recipients may use different email providers. Downside (and deal breaker for me) is no support for forward secrecy by delta chat