Apple’s designs have become so ubiquitous over the past ten years that’s it hard to remember a time when the company was struggling to find its identity. Early in Apple’s existence, the rising star of the industry brought in outside help to figure out how to make its products stand out. In fact, Frog, a design firm with studios all over the world, is credited with many of the earliest design prototypes for Apple’s future products. Of course, plenty of the designs were changed significantly from their conception (or scrapped entirely), but as Frog founder Hartmut Esslinger illustrates in his latest book, Keep it Simple, Apple might never have drawn so much attention without the assistance of his team. Among the stories, Esslinger includes some fascinating imagery of prototypes that never saw the light of day. We’ve included a few below, but head over the to The Verge to see the rest.