SyncFlow – Privacy-Focused SMS/MMS Sync Between Android, Mac, and Web

Show HN: SyncFlow – Privacy-Focused SMS/MMS Sync Between Android, Mac, and Web

Operating in show hn launch, SyncFlow – Privacy-Focused SMS/MMS Sync Between Android, Mac, and Web operates.

Profile

I built SyncFlow to sync my Android SMS/MMS messages to my Mac and web — without relying on Google Messages or any third-party big tech cloud.It runs on a dedicated server with a Node.js/Express API + PostgreSQL backend.The Android app syncs messages, contacts, and call history, and you read/send them from a native Mac app or web client. Your messages never touch Google, Apple, or any third-party cloud.Key technical decisions: - E2EE with Signal Protocol for message encryption - WebRTC for video/audio calls between devices - MMS attachments stored on Cloudflare R2 via presigned URLs - WebSocket for real-time message delivery + delivery status tracking - Firebase Auth for identity only — mess

The company sits in the show hn launch segment, where it competes on its core product or service.

Its current recorded stage is Show HN launch.

Website: sfweb.app