Is that not a fairly simple technology? You're basically measuring latencies (for which there exist very accurate solutions) and accounting for clock drift (again not difficult - USB audio did that many many years ago).
I guess you can get fancy if the devices have microphones but I still think it wouldn't be difficult. Like one man-year worth of work.
Creating a web player that syncs audio across all types of IP devices where you can play, pause, fast forward, seek within a track & more as seen in this video isn’t trivial!
I guess you can get fancy if the devices have microphones but I still think it wouldn't be difficult. Like one man-year worth of work.