Focus groups are so last century. Who needs one when you can tap into legions through social media? That’s what Lays did in its search for a new chip flavor. Visitors to its Facebook app were asked to suggest flavors and names. Not sure what you like? The app rifles through your page, a cascade of ingredients and your photos pouring into the Lays bag on screen. The app then suggests flavors you might like. Apple and brie chips? Delicious.