Wires

"Wires is the first step for everyone with an app idea. Use Wires to create a fast visual note about your idea directly on your iPhone. Whether it’s your first app idea or fiftieth idea, everyone needs a quick, easy place to document it. Wires uses templates, buttons, and shapes that are already familiar to iOS users to create super easy screen mockups of app ideas. Include details of your idea in annotations and then easily export your screens and notes as a PDF to share with anyone. A couple minutes with Wires can help you determine whether or not it’s worth spending hours with a designer or developer making wireframes or prototypes of your idea. Don’t try to make your app idea fit into a text note or scribble it awkwardly onto whatever paper is most convenient. Use Wires to create notes about your app idea that include layouts and text."