Following a test this past summer and a wider rollout in late October that allowed Instagram friends to live stream together, the service today is adding the option for you to request to join a pal’s live stream, just in case you believe your presence is required.
Instagram’s live mode works a lot like Periscope, which allows people to watch a user’s live stream and send comments or hearts. Today’s update allows the live streamer to add a request button on their page so friends can request to jump in on their solo stream if they didn’t invite anyone to go live with them from the start. Once accepted, the stream divides in half (either horizontally or vertically, based on the orientation you’re watching the stream).
Currently, Instagram only supports multi-user live-streaming between two friends, so someone you do not follow back cannot request to be in your stream. But unless you really want someone to join you, the requests might get annoying, so turn the button on at your discretion.