Concept image: Nikola Cirkovic

Concept image: Nikola Cirkovic

I wrote in an earlier opinion piece that 2014 is the year when I expect Apple to finally give in and opt for a larger iPhone display. Assuming I’m right, the question then becomes: what approach will Apple take?

There are two ways of increasing the size of a display. First, you can keep the resolution the same and simply use larger pixels. That’s what happens when a manufacturer makes a 1080P HD TV in both 40- and 50-inch sizes, for example. Both have 1920×1080 pixel displays, it’s just that the 50-inch display has larger pixels.

That would be by far the simplest approach for Apple to take. Provided it keeps the aspect ratio the same as the iPhone 5/c/s, then it can continue to use an 1136×640 display. All existing apps continue to work as-is, developers don’t have to do any work to support the larger display and everyone is happy . Or are they… 


There is, however, a downside to this approach: the display will get just that little bit less sharp. Next time you’re in a store with a display wall full of TVs, approach one of the smaller ones until you can make out the individual pixels. Now back off just far enough that you can’t. Now look at a larger TV at the same distance. Suddenly the pixels are visible.

This is largely an academic exercise. Once the pixel density hits a certain level, the pixels are no longer visible at any normal viewing distance. I’d say 4.5- to 5-inches is the likely range for a larger iPhone (I’m not entirely convinced by the two-size rumors), so let’s take the example of that 5-inch top-end …

If Apple stretched the current 4-inch display to 5 inches, while retaining the same 1136×640 resolution, the pixel density would decrease from 326ppi to 260ppi. Would this still qualify as a Retina display?

Apple has never defined Retina with specific ppi numbers, saying only that it is a number “high enough that the human eye is unable to discern individual pixels at a typical viewing distance.” For an iPhone, Apple considers a typical viewing distance to be 10 inches.


Now let’s compare with the iPad. The iPad Air has a pixel density of 264ppi – coincidentally, almost identical to our hypothetical iPhone 6 with unchanged resolution. And the iPad, says Apple, is still Retina because the typical viewing distance for the larger device is 15 inches.

Well, I’ve just done a little experimenting with my iPhone and iPad and learned two things. One, I actually hold the two devices at pretty similar distances, of 10-12 inches. Two, at even 10 inches, I can’t really resolve individual pixels on my 264ppi iPad Air. Apple could, as far as I’m concerned, design an iPhone 6 with the same 1136×640 resolution as the iPhone 5, and I’d consider it Retina.

For me, then, an iPhone 6 with identical resolution screen in a 5-inch size would be a feasible option.


Now let’s consider the alternative: increasing the number of pixels in direct proportion to the increase in screen size to retain the same 326ppi pixel density.

For the sake of simplicity, let’s assume Apple keeps the aspect ratio the same. That would mean an increase in resolution from 1136×640 to 1420×800.

It’s unarguably a Retina display. The marketing people don’t have to fudge their definition of Retina display, and get to boast that ‘the iPhone 6 has the highest resolution display of any iPhone, with 25% more pixels.’ Customers get the same quality display they had in their iPhone 5s or 5c. Everyone is happy.


Except developers. Just as when the resolution changed from the iPhone 4s to the iPhone 5, suddenly they have to support yet another resolution. All that work they had to do then, they now have to do all over again.

Apple may have built the best phone in the world, but its success is at least as much down to the huge number of high-quality apps as the design of the handset itself. Apple knows how important developers are. There was a huge amount of dismay at the switch in resolution when the iPhone 5 was announced – would it really want to put developers through the same pain again with the iPhone 6?

My suspicion is: yes.

First, while a larger screen is easier to view, it doesn’t buy you any more real-estate: you won’t be able to see any more of your emails. A higher resolution, in contrast, lets you see more of your content at a time.

Second, while Apple could fudge its viewing figure distances, and say – probably quite accurately – that a 260ppi phone display is still Retina, it would be a bit of an embarrassment to have to do so.

Third, while Apple has never gotten involved in pointless specs races – witness it sticking with an 8MP camera, for example, while competitors went as high as 41MP – there’s a big difference between leaving a spec unchanged and launching a new model with a poorer spec. A reduction in ppi from 326 to 260 would not go unchallenged.

Fourth, it’s hard to argue that Apple wouldn’t want to cause its developers grief with a resolution switch when it has already done just that once before.

There is a fifth argument: that iOS has for some time been headed in a direction that makes resolution changes less painful than they might be.


In iOS 6, Apple introduced the concept of Auto Layout. Instead of developers having to specify absolute pixel coordinates for objects, they are able to define a location in relative terms. For example, this object should be centred and at least 20 pixels away from neighbouring objects.

Not all developers adopted it. In fact, probably most haven’t, as there’s been no particular reason to so far. A change in resolution would provide that reason, and they’d then have apps that would play nicely with any future resolution changes.


Then there’s iOS 7. A flat user interface becomes much easier to rescale than one that has pixel-level decoration in the form of shadows, glows, textures and so on. Perhaps Apple introduced the flatness of iOS 7 purely for aesthetic reasons, but perhaps not.

It’s also not all gloom-and-doom for developers: a great many apps are effectively just navbars and tableviews, and adapting those would be a simpler task.

So my view is, yes, we should expect to see not just a larger display size in the iPhone 6, but also a new resolution. Let us know your views – especially if you’re a developer – in the comments.