keychat on Nostr: Keychat relies on relays, but it minimizes their authority to only forwarding ...

Keychat relies on relays, but it minimizes their authority to only forwarding encrypted messages.

Another approach is peer-to-peer (P2P), where the client and server are merged—Briar and Keet are two examples of this model. When both parties are online, P2P communication is relatively straightforward; for instance, voice and video calls can be handled via P2P WebRTC under most network conditions. However, things get trickier when it comes to sending text messages while the recipient is offline. What kind of node should temporarily store the data and later sync it to the recipient once they come online?

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'Unlike traditional messaging apps, Briar doesn’t rely on a central server – messages are synchronized directly between the users’ devices. If the Internet’s down, Briar can sync via Bluetooth, Wi-Fi or memory cards, keeping the information flowing in a crisis. If the Internet’s up, Briar can sync via the Tor network, protecting users and their relationships from surveillance.'

Briar is great, but it requires both parties to be online at the same time to chat.