When shopping in any store that carries national brands, it’s virtually impossible to remember which ones you’re not supposed to buy for which reasons. This one uses palm oil … or was it this one? This brand is “all-natural” but it sprays evil chemicals all over the world. This company kills panda babies. And so forth. You can either hold out for Sunday’s farmers market and not eat in the meantime, or just go ahead and buy the cornmeal from the brand that’s probably in bed with Monsanto.

But now a programmer named Ivan Pardo is putting an end to this misery. Scan a product with his app, Buycott, and it analyzes the insane web of corporate ownership in order to tell you exactly what terrible policies you’d be supporting if you bought that cereal.

Forbes reports:

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Once you’ve scanned an item, Buycott will show you its corporate family tree on your phone screen. Scan a box of Splenda sweetener, for instance, and you’ll see its parent, McNeil Nutritionals, is a subsidiary of Johnson & Johnson.

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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.

There are also positive campaigns — you can support brands that support issues like gay marriage. Given that most corporations are terrible on some issue or another, this may not solve the “I can’t shop at a mainstream store without compromising my principles” problem. But at least you won’t have to guess.