Whenever Apple launches a new gadget with a new screen size, iOS current apps have to be made to fit them. Sometimes, the resolution of an app only needs to be doubled, as was the case with the iPhone 4 and Retina displays. For the iPhone 5s larger screen, developers had to do some work resizing their apps to make them taller. With the iPhone 6 (1334 x 750) and iPhone 6+ (1920 x 1080), Apple has cleverly kept the same 16:9 aspect ratio for its screen, which means current apps will automatically scale up to fit the device.