Watch2Gether - Watch2Gether is an app that allows multiple people to watch the same content simultaneously and interact with each other while watching.
Playo - Organize a local team sports or join a fitness community
Metastream - Watch streaming media with friends
Teammate - Find or organize pick up games and team sports
StreamParty - StreamParty is a watch communiry, that allows you to watch video streams in sync with the people you care about, on multiple services.
Heja - Easily communicate within your sports team