Postcard on the Run
This app allows you to create and personalize your own postcards, using photos that you take yourself. All you have to do is take a photo, personalize it by choosing a border, even add a "scratch and sniff scent" for 50 cents more, type a message, select a name from your address book, and sign your name by moving your finger across the screen. The app then creates and sends a 4x6 glossy postcard for you. You can check if your postcard was delivered by asking the recipient to scan a code on the back of the card, letting you know it arrived.
Cost: $1.49 for a postcard within the U.S., $1.69 to send internationally.
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