Delta Chat drops unencrypted email; adds decentralized onboarding across community relays

Delta Chat, the open-source messenger that runs over encrypted email infrastructure, broke a six-month silence on its blog this week with a batch of long-requested features, including pinned messages that keep announcements, group guidelines, or favorite mini-apps at the top of any chat. The update also brings Apple's Liquid Glass design language to iOS, in-app updates for Android users installing the APK outside app stores, and — perhaps most notably — reactions in channels, letting subscribers respond to posts instead of remaining a silent audience. Smaller refinements also include multi-select for messages on all platforms, a “Mark as unread” option, and noticeably sharper photo sharing.

The bigger story is architectural: two years after introducing nine.testrun.org as a default onboarding relay, the team says it has spent 30 months dismantling that centralization, wary of repeating the practical centralization seen in Matrix and the Fediverse despite decentralization in theory. New profiles now automatically connect to multiple community-run chatmail relays, joining whichever responds fastest, with two more added in the background for a total of three, and incoming messages are fetched from all of them simultaneously. Outgoing traffic falls back to alternate relays if one fails, so a rebooting relay operator no longer interrupts anyone's chats, and users can remove unwanted relays at any time in the advanced settings. No email address appears on profile screens anymore; a profile is identified purely by its encryption key.

The most consequential change is coming next: Delta Chat will drop support for unencrypted email entirely, mirroring [Signal]'s 2022 removal of plain-text SMS. The team cites security, unencrypted email leaks content and metadata to providers, as well as the risk of confusing users in a mixed secure/insecure interface, and the development burden of supporting both. Upcoming releases will make encryption mandatory with no opt-out and turn legacy unencrypted email chats read-only, though the app remains interoperable with any email client implementing modern IETF encryption standards like OpenPGP (RFC 9580) and PGP/MIME. That groundwork feeds into Autocrypt v2, which since May 2026 includes post-quantum cryptography support and will eventually bring forward secrecy to the platform. Users still relying on Delta Chat as an email client are pointed toward Thunderbird, FairEmail, or K-9 Mail.