To check whether you have the livestreaming tool, select Update Status at the top of your News Feed and hit the new Live Video icon (it should display a banner notifying you of its existence). You'll then be able to choose who you want to share your stream with and add a description before broadcasting it to the world. Facebook expects its iOS rollout to take a couple of weeks but remains quiet on when Live Video will come to Android. All we know is that the company intends to expand the feature "soon."