I Built SyncBuds: Synchronized Audio Across Phones with No Backend 🎧

What if friends could listen to the same audio together, perfectly synchronized, while each person uses their own phone and earbuds?

That’s SyncBuds.

📱 One phone hosts a room
📶 Friends join over WiFi or hotspot
🎧 Everyone listens through their own earbuds
🚫 No backend, accounts, or internet required

How it works

The host phone acts as the server and clock master.

Under the hood, SyncBuds uses:

• mDNS for room discovery
• TCP for control messages
• NTP-style clock synchronization
• UDP for real-time audio streaming
• Native Android audio playback
• Jitter buffering and drift correction

The hardest challenge is keeping different phones synchronized despite network jitter and device-specific audio latency.

What works today

✅ Room hosting and discovery
✅ QR/code joining
✅ Real clock synchronization
✅ Host-to-guest audio streaming
✅ Synchronized play/pause
✅ Latency calibration
✅ Auto-reconnect

SyncBuds is still early and completely open source. I’m looking for testers and developers interested in Android audio, networking, Flutter, or DSP.

⭐ GitHub: https://github.com/divyanshupatel17/syncbuds

Feedback and contributions are welcome! 🚀