A friend of mine told me about this iPhone app that every kids church that has self check-in or uses Bible Bucks 2.0 needs to know about. What is CardStar? CardStar eliminates wallet overload by consolidating your membership and rewards cards on your smartphone — letting you access scannable cards, deals and retailer information within a single app. Shop smart with CardStar — storing all of your rewards cards in a single app so you’ll never forget them again, and …