GoKawiilApple's John Ternus details iPhone Duo's 2011 origins in TIME interview
Apple hardware engineering chief John Ternus told TIME that work on a foldable device began as early as 2011, when he and five colleagues filed a patent application exploring batteries and circuit boards for folding electronics. Ternus said he was unimpressed by other companies' earlier foldable phones, calling them 'cheap and crappy,' and described pushing his team to keep refining the iPhone Duo's design even as rivals shipped foldables years earlier. Apple VP Richard Dinh also described how Ternus urged engineers to avoid settling for an adequate surface material, leading to a custom polymer nanotexture surface and a hinge with over 100 precision components.