CardStar CardStar is a dream app! I discovered this app when looking for a simple solution to the problem of always forgetting my library card. You can search by category and add the cards that you use by entering either their number or by scanning them using the Barcode Scanner app. Categories include: Airline, Association, Beverage, Car Rental, Convenience Store, Cruise Line, Drug Store, Entertainment, Gas, Grocery, Gym, Healthcare, Hotel, Library, Local, Museum, Restaurant, Retail, Service, Train, Travel. CauseWorld Check-in apps are all the rage right now with the most popular being Foursquare & Gowalla. However, if you want to use a location based check-in app & make a difference at the same time, then CauseWorld is what you want. In addition to earning badges, you also earn Karma points, 5 points for each check-in. These points can then be donated to a cause of your choices. Donations range from 1 - 200 Karmas. One of my favorites is Donate a Book which, for 100 Karmas,