Syncplay

It enables a group of users who each have identical video files to watch them in lockstep over the Internet. Playback actions such as play, pause, and seeking are transmitted through a shared virtual room so that all participants experience the same timeline. The client can be paired with VoIP tools for chat, and a public server infrastructure is provided for easy connection.

The software supports a range of media players—including mpv, VLC, IINA, MPC‑HC, and others—on Windows, Linux, *BSD, and macOS (version 15 or later). Installation packages are available for each platform, and a command‑line console version exists for Windows. The project is released under the Apache 2.0 license and is free to download.

Typical users are friends, families, or remote teams who want synchronized viewing without streaming the file itself. By handling only control signals, it works with locally stored media and requires no additional bandwidth beyond the coordination traffic.