This is twitter's live video streaming app. Send or watch live videos from users all over the world. Its as simple as downloading the free app, signing in with your twitter account...and you're off and running. The app uses your phone's camera and microphone to capture what is happening around you and share it online...in real time. Viewers also have the ability to comment and “like” your live stream. When you start recording, a link will pop up in your twitter feed and your friends (*who also have periscope) will receive an alert that you are broadcasting. When you end your Persicope, a link to “re-watch” the video is posted to your twitter feed. To watch live or archived streams, you must have the app on your phone. So far, there IS a way to emulate the Android app on your PC, but it's complicated, so for all intents and purposes, get the app on your phone. It's free on iTunes and GooglePlay.