Flickcall - Flickcall is a privacy-focused browser extension to watch movies & TV shows together.
Metastream - Watch streaming media with friends
Hyperbeam - A better way to watch together online
Watch2Gether - Watch2Gether is an app that allows multiple people to watch the same content simultaneously and interact with each other while watching.
Jelly Party - Watch anything together.
Togetherly - Watch Youtube with friends