Sponsorship is playing a critical role in the launch of the Brabble smartphone app.Brabble is promoting the app through a rolling spring marketing campaign that includes rock music festivals, EDM conferences, urban music tours, college marketing programs and celebrity tie-ins.Ties include the Rock on the Range music festival in Columbus, Ohio; Rocklahoma presented by Bud Light in Pryor, Okla.; the Winter Music Conference in Miami Beach, Fla. and Iggy Azalea’s 12-stop tour.The privately-hel...