You can scan the barcode on any product and the free app will trace its ownership all the way to its top corporate parent company.

Even more impressively, you can join user-created campaigns to boycott business practices that violate your principles rather than single companies. One of these campaigns, Demand GMO Labeling, will scan your box of cereal and tell you if it was made by one of the 36 corporations that donated more than $150,000 to oppose the mandatory labeling of genetically modified food.

 

In her keynote speech at last year’s annual Netroots Nation gathering, Darcy Burner pitched a seemingly simple idea to the thousands of bloggers and web developers in the audience. The former Microsoft MSFT +0.39% programmer and congressional candidate proposed a smartphone app allowing shoppers to swipe barcodes to check whether conservative billionaire industrialists Charles and David Koch were behind a product on the shelves.