The functionality is slowly being rolled out and is currently only available in the US, according to the company. The ‘Watch Party’ feature will accommodate up to 100 viewers in a single party, but each person must have a Prime subscription located in the USA.  The biggest downside right now is that there are still no movies and TV shows available for rent or lease that can be downloaded in Watch Party.  Watch Party is a private party that helps the host to bypass complete integrated replay controls and a chat option to converse with the other visitors so everyone can become part of the watching experience of the founder as long as they have a Prime account.