The Design Choice That Instantly Made the iPhone Duo the Best Foldable on the Market

Every product was carefully curated by an Esquire editor. We may earn a commission from these links. Here’s how we test products and why you should trust us.Apple5 min readI’m sure you know the basics by now. If you’ve spent any time on the Internet this week, you’ve seen that Apple released its long-rumored foldable iPhone, dubbed the iPhone Duo. It’s the biggest and most expensive iPhone ever, and in his inaugural September keynote, new CEO John Ternus called it the “most transformative iPhone since the original.”Reactions have so far been mixed. In my scrolling, it feels like I’ve seen more negative than positive, but negative is the tune for which the Internet is strung. I had the exact opposite experience at the Steve Jobs Theater seeing Wednesday’s announcement in real life. These events are Apple home games; people around me were openly gasping, cheering, clapping. Ternus got a standing ovation before the presentation, not after.AppleI think all the early chatter has gotten it a bit wrong. Sure, we all want to know the consumer essentials: The starting price is $1,999, the IP68 water and dust rating is achieved with a 3D printed titanium hinge cover, and the cameras are good but not as good as those on the Pro. But I think that “most transformative iPhone since the original” comment is too serious to gloss over.When Apple makes its most “transformative” products, it always has to do with the interface (the place where you, the human, interact with a device). The company has always succeeded with simplicity, paring down to only the essentials. The original Mac’s graphical interface, the iPod’s scroll wheel, the iPhone’s touch screen—none was the very first to do the thing, but all were the first to perfect it. Apple’s greatest strength is making devices that are instantly intuitive; they just feel right.This release’s big interface choice—which I haven’t seen mentioned much elsewhere beyond cursory sentences about the “passport shape”—is the aspect ratio. The phone has a √2:1 (that’s the square root of two by one, or 1.414:1) aspect ratio. Okay, what does that mean, nerd? I’ll keep this as plainclothes as possible. It is a unique rectangular aspect ratio because it is the only one that can be infinitely folded into two rectangles of the exact same size, with the exact same aspect ratio of the original rectangle. That means the small outside screen exactly mirrors the size of half the large inner screen, but it also exactly mirrors the total aspect ratio of the entire large inner screen.AppleSo why should you care about this? Because it’s a simple design choice that no other foldable phone has chosen, and it instantly makes for a more natural experience that outpaces the rest of the market. This is the thing from this launch, because it’s perfectly representative of the Apple ethos.In this case, that natural experience is the symmetrical scaling of apps as you open, close, or partially open the phone. It’s the first time I’ve used a foldable phone and thought, “Oh, I would make the jump for this.” On competitor foldable phones, the inner and outer screens function completely separately in my brain: Outer is for vertical scrolling (like on TikTok), inner is for horizontal (watching movies), and never the twain shall meet. But here, Apple makes a dual-screen experience that is totally cohesive. I could play around in Maps, open the phone to double the size, drop the map to half screen, and pull up a browser for a search query. At every point in that process, you’re working with screens and half screens of the exact same proportional shape. You don’t have to be taught how to use it. It just feels right.And I actually see this as a bold choice for Apple, because this specific aspect ratio is pretty much untouched in consumer electronics. Chinese smartphone juggernaut Xiaomi’s new 18 Fold is the only thing like it. Now we have two of the top three smartphone sellers in the world adopting the shape. A shape that is also very close to the aspect ratio of IMAX, which in its truest form is projected at a 1.43:1 ratio that is only marginally taller than that of these phones. Other people on the Internet used this to joke that we’ll all be getting IMAX optimized for iPhone. Obviously that’s not serious, but this rise alongside the IMAX push at the box office does make me feel that this might be the screen shape everything is trending toward.In the 48 hours since holding the phone, I find myself scrolling on my current phone and visualizing how whatever I’m doing would be easier on the Duo. We can debate the price tag and whether Apple, Samsung, or Google has better nuts and bolts in a foldable phone, but I’m confident that Apple’s shape is the one that will stick.AppleOkay, What Else Do You Need to Know? Now that I’m done musing on shapes, here’s the nitty-gritty.Preorders for the phone begin Friday, October 16, with availability beginning Friday, October 23.The main talking point, other than the simple fact that it folds, is that Apple Intelligence is getting more integrated. It is, essentially, like any other AI tool that any other tech company is pushing on you. It can take prompts from voice or text to scrub your on-device data for texts; it can summarize emails; it can help you search for information. The cool thing, I will say, about Apple’s AI is that it either runs completely on device or in a private cloud. Not even Apple, so it says, has access to what you’re doing on there.As for the guts, it’s the usual. The Duo is faster, stronger, and more efficient than the iPhones that came before it. The camera is incredible, with a new propped-up auto-selfie function, but it is below the level of the 18 Pro and 18 Pro Max—as was expected.That’s why I come back to the shape. It is the one true “transformative” design choice. I’m not sure if the entire Apple flagship lineup will go folding over the next decade, and I’m not sure if it will even stay in this aspect ratio that I love so much. But I am sure that whatever direction Apple goes in, the rest of the industry is following.