We spent nearly one year building a parallel version of Paper that, under the right conditions, could have passed for a shipping application. So why spend so much time building prototypes?

Simply put, the level of detail we covered was necessary. In our redesign, we replaced several beloved elements of Paper on iPad, including the journal view and gestures that our community was familiar with. We didn’t take these changes lightly, so through rigorous prototyping, testing, and iterating, we designed a new way to navigate the app on iPhone and iPad that preserved the heart of Paper as the place for your ideas.Building the prototypes let us put our ideas in front of users early on so we could adjust every element of the app until it felt just right.

The process of refining Paper never stops as we continually adapt to new environments. Over time, operating systems gain and lose functionality, needs evolve, behaviors change. Through these changes, our mission has stayed the same: to help get your thoughts down so you can take projects to the next step with tools that are at once familiar and intuitive.

Source: Prototyping Paper on iPhone, Part II — The Open Studio: A Blog by FiftyThree