I've been a fan of Major Lazer since the beginning & nothing surprises me when they drop something new & exclusive. Major Lazer (consisting of Diplo, Walshy Fire & Jillianaire) & Dutch duo Showtek (Sjoerd Janssen & Wouter Janssen) came together to make a promising track. Believer is one of those tracks that you can't help but listen to. Especially on Spotify. Since it's the only stream you can find the full track on. Out in the open that is. You can listen to & buy the track here. I'm pretty sure Major Lazer & Showtek respectively will be touring in a city near you.
*Update* 10/04/16 – Believer can be found everywhere for purchase & stream.