Question: "Contagious Love" is a song by American singers Bella Thorne and Zendaya, Zendaya's music career began in which year, when she released the single "Swag It Out", followed by the single "Watch Me" (with Bella Thorne); the former was released by an independent record label?
Sentence (from "Contagious Love"): It was released as promotional single on February 14, 2013 in United States and February 19, worldwide.
Relevant evidence: No