Roll Together only sends the data needed to synchronize videos between users watching together.

What data is transmitted:
1. Video playback state (playing/paused)
2. Current video timestamp (in seconds)
3. Room IDs for synchronization

Key points:
1. Data transmission is temporary and session-based
2. No permanent storage of user data
3. No third-party data sharing
4. Users can disconnect anytime
5. Local preferences (colors) stay in browser only