Delta Chat
Messenger using email as transport—chat over your existing IMAP/SMTP accounts.
Why it is included
Creative open protocol reuse: no new silo, just modern UX atop standards.
Best for
Privacy-minded users who already own email infrastructure.
If you use Windows, Mac, or paid tools
Messaging alternative to WhatsApp Business, Telegram, and Signal for email-account-based chat.
Strengths
- Federation via email
- No vendor lock chat network
Limitations
- Deliverability depends on mail providers
Good alternatives
Matrix · XMPP
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