LOS ANGELES (GN) Rihanna has seen off competition from Beyonce and Katy Perry to be named the most influential pop star. The Umbrella hitmaker came top in a list by 4Music following an analysis of social media activity, airplay and press coverage, while the Crazy In Love hitmaker is in second place. Boy band One Direction bagged third, Perry lands at number four, and Justin Bieber rounds out the top five.