Up Periscope! Lessons in live-streaming
![An officer looking through the periscope in the control room of a U.S. Navy submarine in World War II.](https://beisdigital.blog.gov.uk/wp-content/uploads/sites/111/2016/03/Submarine_periscope-620x410.jpg)
Periscope is a relatively new live-streaming app from Twitter, but it already has nearly 2 million daily users watching 40 years of video per day.
Periscope is a relatively new live-streaming app from Twitter, but it already has nearly 2 million daily users watching 40 years of video per day.