Periscope is a live streaming social media app acquired by Twitter in 2015 that allows users to broadcast live video from their mobile devices. In its first year, Periscope saw over 200 million broadcasts and over 110 years of content watched daily. Strengths include notifications when people you follow broadcast, live commenting for interaction, and the ability to broadcast from anywhere globally. Weaknesses include the lack of an on-screen timer and comments fading quickly. Periscope is used by news organizations like CNN and provides an efficient way to broadcast events in real-time.