The synchronized viewing is done through a chat-like room so you can.Play local (with shared playlist) or online videos supported by youtube-dl (on my computer this worked with mpv, but it didn't work with VLC).You can choose to use one of the free public Syncplay servers, or you can host your own public or private Syncplay server, be it on Windows, macOS, Linux (including Raspberry Pi). So when one viewer seeks, pauses or unpauses a video, this is applied to all viewers / media players that are in the same Syncplay room, on the same server. The application synchronizes the position and play state of the media player over the Internet, allowing all viewers to watch the same video in the same time. It supports mpv, VLC, MPC-BE and MPC-HC, with each user being able to use any of these media players. Syncplay is a free and open source tool to synchronize media players with remote friends to watch videos together, available for Microsoft Windows, macOS, Linux and *BSD.