Doesnt use the official in app purchase methods. You have to pay to advance levels which in not disclosed in the description. Beware people, turn off your "in app purchase" mode in your device settings. This will insure that you have to enable that setting for in app purchases and to prevent your children from making any accidental purchases without your knowledge.
ClubUgly about My First Games: Find the Differences - Free Game for Kids and Toddlers - Kid and Toddler App