The app, developed by Glamour magazine and technology company, SpyderLynk, enables readers to “Like” brands on social-networking sites, obtain discounts, and buy products directly from print advertisements. More than 25 advertisers have participated in these issues with special offers for readers who “Like” their brands. Advertisers feature “Social SnapTags” or “Buy it Now” 2-D mobile bar codes in their print ads, which readers can scan and then “Like” on Facebook in exchange for deals. To encourage participation, advertisers created mobile-marketing campaigns that feature sweepstakes to win free trips to NY, discounts, free overnight shipping, and other offers.