A report from earlier today claims that the iPhone 6 will feature a 1704×960 resolution display with a much higher pixel density. The 1704×960 display resolution is thrice the base resolution (568 x 320 pixels), and the transition to a 3x screen resolution from the current 2x Retina displays would be quite smooth.
Just like the non-Retina to Retina transition, the 2x to 3x transition would involve a proportional scaling up of image assets in unoptimised apps, and would require developers to issue updates to their apps to supply @3x image assets as well.
A MacRumors forum poster visually explained that scaling up 2x image assets for the 3x iPhone 6 display would look much better than what 1x assets scaled up to 2x looked like.
Keep in mind however that unlike with the @1x -> @2x transition we had in 2010, this time we’d only have a 50% enlargement rather than 100%.
The thing is, a 50% enlargement with interpolation doesn’t look worse than a 100% enlargement with pixel-doubling, despite the loss of details due to the interpolation. [...]
As you can see, older non-@3x-optimized apps would actually look better on an @3x iPhone than non-@2x-opitmized apps did on an @2x iPhone. Add to this the fact that the screen’s pixel density would be higher this time around, and the perceived image quality difference would be even smaller.
iOS 8 will presumably automatically handle optimising system-drawn elements like text, vector icons, etc., for the higher-resolution screen, so that it looks sharp and crisp. This optimising will be done without developers having to update their apps.
Sources say that core user interface elements, from iOS functions like the Home screen, Notification Center, and Settings panels, will simply appear like larger versions of those functions on the current iPhone display. However, sources also say it is likely that developers and Apple itself will be able to optimize some applications to better utilize the larger screen area. It is possible Apple could revamp the Home screen and other functions between now and this fall’s launch.
To see how the existing iPhone interface would scale up, 9to5Mac tweaked the iOS Simulator to run at 3x mode.
Here’s how the home screen would look on the higher resolution iPhone 6 display. As you can see, the number of apps in the home screen grid remains the same, but their size increases.
Similarly, here’s how the Notification Center would look on the larger screen. Since the interface is mostly text, Apple would need to make very few tweaks to get Notification Center ready for the iPhone 6:
The Calendar app on the other hand makes use of image assets for search, add and list buttons, and they will appear pixellated until Apple uses @3x images for the buttons:
Apple’s known to make transitions between new screen sizes, new resolutions as easy as possible for developers, and this @3x approach is the easiest for developers, because apart from providing high-resolution image assets, they won’t have to make any other layout changes for their apps. The transition also ensures that users would get the best experience possible with apps not optimised for 3x mode.
Let us know what you think of Apple’s transition strategy to 3x screen resolution in the comments below.