Apple may be adding support for a “triple-resolution” Retina Display into iOS 8 according to a new discovery by iOS Developer James Thomson. In a series of tweets this afternoon, Thomson indicated that he had discovered a bug in iOS 8 beta 5 that loads a 3X asset instead of a 2X asset, and further explained that this only happens specifically with 3X assets and not other resolutions like 4X, suggesting this indicates a deliberate decision in the iOS 8 code, rather than a matter of simply selecting the highest-resolution asset available.
Basically, it looks like UIImage has had support for @3x retina images added to it in iOS 8, and/or there is a bug in image loading. — James Thomson (@jamesthomson) August 29, 2014
Mark Gurman of 9to5Mac originally reported in May that Apple was testing a 1704×960 screen resolution for the iPhone 6 that would be achieved by tripling each pixel from a “base resolution” of 568 x 320.
Daring Fireball’s John Gruber added his speculation earlier this week suggesting different screen resolutions may be used and that the higher resolution would only apply to the larger 5.5” iPhone 6 in order to maintain a proper Retina Display pixel density. It still remains unclear what hardware Apple may ultimately intend to use this on, since although the iPhone 6 is scheduled for release next month, it is expected that new iPad models will also be appearing during the iOS 8 lifecycle, including a rumoured 12.9” iPad which may also require a higher pixel density for the larger display.