Apple iPhone Duo review: Return to XS

For as long as foldable smartphones have been around, consumers have been waiting for Apple to release an iPhone that incorporates the same cutting-edge display technology found in the likes of the Samsung Galaxy Z Fold and Motorola Razr. 

Safe to say, the iPhone Duo has been a long time coming. Even at a glance, the story that it’s been worth that wait is a legible one. The case that this is the most meaningful update to the modern iPhone lineup since Apple first built out that roster with the iPhone XS, iPhone XS Max and iPhone XR back in 2018 is a compelling.

After years of steady refinements on a familiar blueprint, the iPhone Duo feels like something truly different – even if the influence of Android-based devices like the recent Galaxy Z Fold 8 is especially easy to see. That distinction doesn’t always translate into the best experience, but Apple’s first foray into foldables feels like it raises the bar for the category writ large.

All of this is to say that while the iPhone Duo isn’t perfect, it does mostly live up to the hype.

Arriving almost a decade after Samsung's first set the bar with the Galaxy Fold, Apple's foldable iPhone wastes no time in pulling all the usual tricks when it comes to feeling as expensive as its premium price-suggests.

With a passport-sized design akin to the new Galaxy Z Fold 8, the iPhone Duo features a 5.4-inch cover display on the outside and a 7.6-inch screen on the inside. Both screens on the iPhone Duo are Super Retina XDR displays clocked at 120Hz and clad in Ceramic Shield 2. The larger one also has a custom nano-texture finish for added durability and readability. It manages to fit neatly into the niche of looking unlike any other foldable on the market, yet also clearly an evolution of the broader iPhone aesthetic. 

All told, the form factor here is similarly slim to the iPhone Air at just 5.2mm but relatively heavier at around 254g. But after years of Samsung working to steadily slim down its foldables, the iPhone Duo has a heft to it which some may find undesirable. There’s something to be said for how this weight makes the device feel literally more significant or premium. However, at the same time, this handset feels like a handful in more ways than one.

Those physical characteristics might not be the only thing that drags down your enthusiasm though. While the glitzy design is one of the biggest things that the iPhone Duo has going for it, there are a few devils in the details that dog the overall experience of using it. 

For instance, take the selfie camera on the cover display. In a pinch, it’s plenty usable. However, whenever I was in a situation that allowed for it, I found myself opting to open the Duo up and rely on the internal screen instead. The external display is a little too small to rely on when taking photos, but shifting to a larger one makes the device writ large a little more unwieldy to use as a camera. 

For what it’s worth, there are a few perks you’re missing out on here compared to what the iPhone 18 Pro and iPhone 18 Pro Max offer. For instance, there’s no Face ID. Instead, the iPhone Duo relies on a Touch ID fingerprint sensor that’s built into the power button. This isn’t a massive hassle to use, but it does often make for an experience with more friction than the average iPhone. The absence of the action button isn’t as noticeable, but these small omissions do add quickly to the sense that a few things have been lost in translation when it comes to bringing the modern iPhone experience to a foldable form-factor.

This brings us right to the elephant in the room, and the camera on the back of the iPhone Duo. The setup here is a dual-lens one, which sees the 48MP wide lens found on the iPhone 17e paired up with the 48MP ultrawide one found on the iPhone 18 Pro.

Unfortunately, the 48MP telephoto lens found on the latter has been lost somewhere along the line. In exchange, you get not one but two selfie cameras. The one found on the external cover display is only 12MP but comes with Apple’s Centre Stage, which promises to help that humble hardware deliver better results. Meanwhile, the internal display on the iPhone Duo features an under-display camera that is invisible when not in use. At face value, this is a very nifty inclusion. No other iPhone has this feature, so it does fold nicely into the futuristic vibes found here, and while I was worried about the quality of the camera given how mediocre similar setups have fared over on the Android side of things, the reality was a little better than I expected.

Unfortunately, the same can’t be said for the main camera on the back of the Iihone Duo. While the flexibility of the camera setup here is in of itself impressive, the results it delivered were a little underwhelming. I just didn’t find myself as dazzled by the photography that the Duo delivered, and I found the lack of additional zoom to be a frustrating constraint. 

The iPhone Duo is hardly the first foldable to fall short on this particular front, but it’s disappointing all the same. Sure, you might mostly be paying the premium found here for the foldable screen but if you’re spending this much on a phone, you should expect to have a better camera on the back of it. 

To see what the camera on the iPhone Duo can do fresh out of the box, check out the image gallery below.

Under the hood, Apple's first foldable comes powered by the same A20 Pro found in its siblings. Unsurprisingly, the performance that processor delivers is as good here as there – which is another way of saying that it’s about as fast as you can expect to find in a modern smartphone. 

Apps loaded fast, and games ran like a dream – even more visually demanding ones. I can’t say that this performance was all that much faster or slower than it was with the iPhone 18 Pro, but at the same time I can’t say I had all that many complaints about the hardware side of things.

The software situation was a little less rosy, however. The iPhone Duo boasts a redesigned version of iOS, which moves navigation elements to the side, stacks dock functionality into collapsible menus, and offers better support for multitasking and app continuity across the two displays.

If you’re sticking to the stuff that sits within Apple’s own software ecosystem, this setup works pretty well – even if it does require some getting used to. As soon as you wander off the beaten path though, you’ll likely run into trouble. It felt like with every other app I installed on the iPhone Duo, it was a roll of the dice as to whether the interface would be aligned to the vision that Apple has for how software should work on this particular device or whether I’d be stuck with an experience that was significantly well short of that. 

Sometimes, apps would load at the wrong resolution or aspect ratio. Other times, they’d run fine – but vast chunks of the iPhone Duo’s tablet-sized display would be left blank. As someone who tested their fair share of Android tablets, these software woes weren’t entirely unfamiliar – but neither were they welcome.

If you are looking to splash the cash on this particular device, chances are that the idea of having one device that does it all is a big part of the reason why. The hardware here is well-primed to deliver on that promise, but the software experience isn’t quite as far along. At least, right now. That situation will likely improve over time, but it’s definitely worth keeping in mind if you’re considering getting in early when it comes to Apple’s foldable smartphone. 

For what it’s worth though, the iPhone Duo did deliver surprisingly impressive results when it comes to battery life. According to Apple, the cover display on the  iPhone Duo can deliver around 31 hours of continuous video playback while its big brother ups the ante to 44 hours. In practice, I had no issues making it through two days of typical usage on a single charge. I’d usually end up finishing my work day without around 60% charge remaining.