The secret to Tinder's success isn't that they use a swipe-based interface. It's that they solved one of the biggest pain points in dating: users never have to talk to anyone that hasn't already expressed mutual interest in them. Since the app discloses romantic interest only after both parties have reciprocated, Tinder offers a fundamentally better way of meeting new people than has existed previously. That was a game-changer for the entire dating scene, and that is why they are successful.