If you’re sick of grocery store rewards cards clogging up your wallet, and you love whipping out your iPhone in public, have we’ve got an app for you. CardStar lets you punch in all your reward cards into your iPhone. At checkout, just click the CardStar icon, select the merchant from your saved list, and show the screen. They can scan the barcode right from the image. Usually $.99, the app is currently free for a limited time. A handy way for iPhone users to reduce clutter and fumbling for rewards cards when shopping.