Facebook live streaming feature is now available to everyone in the US who owns an iphone.
To share live video, users simply tap on Update Status and then select the Live Video icon. Users can write a brief description and choose the audience they want to share with before going live.
During the broadcast, users will see the number of live viewers, the names of friends who are tuning in and a real-time stream of comments.

When users end the broadcast, it will be saved on their Timeline like any other video, which can then be deleted or kept for friends to watch later.
Also, users can discover live videos from their friends and public figures you follow right in News Feed. While watching a live video, user can tap the Subscribe button to get notified the next time the broadcast goes live.
In the coming weeks, the live video sharing feature will become available to all Facebook users across the world.
Source http://www.timigate.com/2016/01/facebook-live-streaming-opens-to-more.html#more