It's an app that can integrate with a lot of streaming services(officially) and has a built-in torrent client(that does nothing). (You know, all of this so that they can be accessible on all platforms, etc. torrenting isn't viewed kindly by platform makers) With the help of third party plugins (such as Torrentio) stremio now has access to systems where you can integrate with torrent sources so that when you browse for your movie, you can also see torrent sources and with the help of the built in torrent client, you can also stream them. Stremio has casting support and apps for all devices, even TV. It makes it really easy to watch movies easier and in better quality than any streaming service. It also keeps track where you last were in your movie so you can resume, the same thing for shows, also has many other useful extensions that streaming services don't support, such as Trakt.tv integration, or browsing curated lists of movies and shows from anywhere, as well as integrating with other sources outside of torrents such as providers holding archived materials.