When Amazon launched Watch Party for Prime Video last year, it only made the option accessible on desktop browsers. Now, the e-commerce giant has expanded support for the feature, allowing you to host or join a Watch Party on Fire TV devices. While Amazon didn't make a big announcement for the feature's arrival on the platform, it updated the list of compatible devices on Watch Party's FAQ, as noticed by XDA Developers. The section now says that you can co-watch with friends and fellow Prime members on a Fire TV device within the Prime Video app.
You still can't co-watch movies and shows with friends on mobile, but you can access the chat section of a Watch Party when you update to the latest version of the Prime Video app for phones and tablets. That'll give you an easy way to talk to other participants without access to a computer, as well as an easy way to create and share Watch Party invites.
Amazon originally launched the feature on Twitch back in 2019, allowing streamers to watch videos with their viewers. The version available from within Prime Video itself is more suitable if you're not a streamer and just want to watch with people you're close to. All participants in a party must also have Prime subscriptions, though, and they must rent or purchase the movie or show the host is watching.