Periscope is an app recently bought and then launched by Twitter..
It basically lets anyone with the app on their phone broadcast or “live stream” anything.. utilizing the camera on the device. People who follow on Twitter get a notice when the person goes live with something.. and then you can watch.
I became kind of addicted to it during the recent Stones tour.. the shows I couldn’t go to I could watch live on my computer and even pick which “camera” to watch as there were many to choose from as the app became more popular as the tour rolled on. Mixed feelings about it though, as I am not one who enjoys people holding up cell phones at concerts… A large stadium show is one thing.. but a smaller inside venue not so much.. Also wonder how welcome it is by the artists as I could see it affecting ticket sales and making bootlegs etc.
Very cool technology though.. especially for behind the scenes stuff like the studio footage..