I never saw A Scanner Darkly but I just watched the trailer and now I really want to. These scanners are a bit different. They enable users to scan the barcode of food items in the grocery store (and sometimes cosmetics) to get ingredient lists and ratings on how "healthy" the food is for you. They also provide explanation on why certain ingredients are less advisable to consume. Yuka owns a staggering 85% of the new install market share. Wired reported that it is so popular in France (native country) that "French supermarket chain Intermarche announced the reformulation of 900 recipes for its own brand products to remove additives and cut sugar and salt to improve their scores." I've now used Yuka several times while shopping and enjoyed the experience. Yuka accepts IAPs for a paid member version. It has generated about half a million dollars over the past 365 days.