Facebook has annoucned that it is expanding its live video sharing feature to all iPhone users in the U.S. The feature allows you to broadcast live directly from Facebook's iPhone app, and choose who to share it with, be it only your circle of friends or the public at large. People can comment on your broadcast in real time, as well.
To share live video, tap on Update Status and then select the Live Video icon. You can write a quick description and choose the audience that you want to share with before going live. During your broadcast, you'll see the number of live viewers, the names of friends who are tuning in and a real-time stream of comments. When you end your broadcast, it will be saved on your Timeline like any other video, which you can then delete or keep for your friends to watch later.
When your friends or celebrities you follow on Facebook start broadcasting, their video will appear in your timeline. You can hit 'Subscribe' during a video to get a notification the next time the broadcaster starts streaming.
Facebook is working to bring live video sharing to the rest of the world soon.