Use:  Easily create rough iPhone app prototypes

POP App allows publishers to sketch out app prototypes on paper (or online), upload photos of the sketches and then animate the action to see a rough version of the app in action.   After sketching and uploading photos of a storyboard, users can create “link spots” within the app to simulate the user interface.  Transition effects include basic, next, back, rise and dismiss.   You can then share the prototype with others to try out on their iOS device or Web browser (Android versions are in the works).

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