Seca Messages

Seca Messages is the messaging app of the Seca suite: Contacts, Phone and Messages, three apps sharing one Material 3 Expressive design, built for privacy. They run on any phone with Android 12 or newer, with or without Google, and are at their best on GrapheneOS. In English, French, Spanish and Polish.

Seca Link: end-to-end encrypted

• Between two Seca phones, messages travel encrypted with the Signal protocol (libsignal, post-quantum PQXDH), bypassing the carrier.


• No account, no Seca server: encrypted messages travel through public Nostr relays, which see neither who writes nor what is written.


• Two contacts connect through an invisible SMS; everything then goes over the Internet.


• Read receipts and typing indicator, each of which can be turned off.


• Safety number to compare, or to scan as a QR code.


• Encrypted photos and voice messages; the microphone is asked for only when you record one.


• Four public relays are set by default (relay.damus.io, nos.lol, relay.primal.net, nostr.mom) and the list is yours to change.


• Off by default: without Seca Link, the app does not use the Internet.

SMS

• MMS: a picture message sent to you arrives and is shown in the conversation, with the words sent alongside it. Sending one is not possible yet, nor are group conversations carried over MMS; both are being worked on. Photos sent through Seca Link are not affected.


• Conversations with your contacts' photos and profiles, search across every message.


• Reply from the notification, scheduled messages.


• Verification codes copied in one tap and erased automatically after a while.


• Advertising texts filed as spam.


• Pinned and archived conversations.

Also

• Password-encrypted backup.


• App lock, and a hidden preview in recent apps.


• Wallpaper colours or Seca palettes, dark theme.

No ads, no trackers, no account. Open source.

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