CardStar is a free app that's designed to help you thin out your wallet or key chain, by replacing all of your discount, reward, and membership cards with bar codes. CardStar requires some work up front, as you have to enter your identification numbers by hand for each card. The app currently supports more than 130 companies, from popular grocery and drug stores to gyms, airlines, and libraries. You can also use the app's "advanced" mode to enter cards for companies that aren't listed.
The developers behind CardStar say that the app works better with handheld scanners rather than flatbed models (with your device held stationary, almost perpendicular to and approximately 5 inches from the scanner). Users have reported varying degrees of success with the app--so don't throw out your old cards until you've taken CardStar out for a test drive. Overall, this app shows great promise, but we look forward to further updates that provide more predictable performance and a longer list of supported companies.