Instagram has been testing 15-second video ads for a few months now, but its new units officially went live yesterday with four brands: Disney, Activision, Lancome, Banana Republic and CW. Disney’s ad sees characters from its Big Hero 6 film posing for selfies, while Activision’s is a clip from a live-action ad for its next Call of Duty game. “Our audience is becoming increasingly mobile-centric, and Instagram is a mobile-centric platform,” says Activision’s head of digital and social media Jonathan Anastas. He also talked about the anticipated reach of the ad: Activision expects it to be seen by 2m users initially, with hopes that they’ll then share it on. AdWeek reports that Instagram is taking a hands-on approach to video ads, making sure brands don’t simply take 15-second slices out of existing TV or web commercials.