Apple iPhone Duo vs. iPhone 18 Pro (Max): Which one to get?

Apple’s relatively stable smartphone line-up made it easy for people to figure out their upgrade path. The company would occasionally throw in a curveball like the iPhone Air or the iPhone 17e, but for the most part, people didn’t spend much time wondering which model to pick. Vanilla users got the new vanilla iPhone, Pro users got the new Pro.

But now the iPhone Duo has arrived, Apple’s first foldable. Obviously, Android foldables have been around for a while now, so this isn’t a completely unprecedented experience. Still, for Apple die-hards this could be their first foldable.

At a glance: iPhone Duo • iPhone 18 Pro

Wouldn’t you be better off with an iPhone 18 Pro or an iPhone 18 Pro Max, though? We would hardly call them exciting, but the iPhone Pro formula was near perfect as it was – the 17 Pro and 17 Pro Max ranked second and third in terms of global sales in Q2 this year, losing out to only the cheaper iPhone 17.

Let us start with the comparison with numbers that hit you right in the wallet. The iPhone Duo starts at $2,000, while the iPhone 18 Pro Max starts at $700 lower and the smaller iPhone 18 Pro is $800 cheaper than the Duo. You can see the price breakdown for other regions below.

While it’s not the first foldable, the iPhone Duo offers a fairly unique experience. It’s a wide foldable and there just aren’t many alternatives, especially not in North America. And indeed, in Europe and most of the rest of the world, as Xiaomi hasn’t announced when the Xiaomi 18 Fold will be available outside of China. This leaves only the Galaxy Z Fold8.

While this isn’t about the Z Fold8 – we have another article that focuses on Samsung’s wide foldable vs. the iPhone Duo – we should mention that the Duo supports using a stylus on its inner display and that same display is unblemished by a camera punch hole. These things used to be true for the Z Folds too, until Samsung dropped the stylus digitizer and the under-display camera with the Z Fold7.

Stylus or no stylus, the 7.6” 4:3 inner display on the iPhone Duo is built for multitasking – this is essentially an iPad mini in your pocket. And while, yes, you can get split screen on the 6.9” iPhone 18 Pro Max display too, it’s just not as good. By our calculations, the internal display of the Duo has a surface area (not accounting for the rounded corners) of 175cm², while the Pro Max display covers 117cm² and the iPad mini stretches out to 204cm².

The 5.4” cover display may sound small, but remember that it has a fairly stout aspect ratio. The Duo is a whopping 84.1mm wide, so it’s not great for one-handed use. The 11.3mm thickness and 254g of weight make the Duo chunkier than most phones out there, even most foldables. The iPhone 18 Pro Max is 8.8mm thick and weighs 249g. The iPhone 18 Pro is even lighter at 211g of weight (and has the same 8.8mm thickness). The small Pro is more pocket-friendly and it is certainly easier to use with one hand. Not that the Duo would have problems fitting into pockets, but one-handed use is definitely an issue.

The Pro models have better cameras. They have a 48MP main module with a large 1/1.28” sensor and sensor shift OIS. This is similar enough to the Duo main camera, but the Pros have variable aperture – f/1.4-f/4.0 compared to a fixed f/1.6 aperture for the foldable.

More importantly, the Pros have a highly capable 48MP 4x/100mm telephoto module, while the Duo has to rely on the in-sensor zoom from the main camera. All three models have the same 48MP 120° ultra-wide camera.

The foldable form factor of the iPhone Duo allows you to take selfies with the main camera, which is pretty cool. It does require you to open the phone, though. If you just want to snap a quick selfie, the two Pro phones have 18MP sensors with depth detection by the Face ID system, while the Duo only has a 12MP sensor and no depth sensor.

The iPhone 18 Pro Max (eSIM variant) has a 5,567mAh battery, which promises to last up to 30 hours of regular use (official stats). Meanwhile, Apple’s estimations put the small iPhone 18 Pro (4,288mAh for the eSIM variant) on par with the iPhone Duo – both are expected to last 24 hours on a single charge.

We will conduct our own battery tests on the new iPhones once we get our hands on them. But for now, let’s look at Apple’s video playback stats. The Pro Max lasts an impressive 45 hours, while the small Pro only manages 36 hours.

For the iPhone Duo there are two numbers. It can play video for only 31 hours when using the larger 7.6” inner display or for a solid 44 hours when using the smaller 5.4” cover display. Again, we’ll test it, but we expect that the Duo will be a battery champ if you restrict yourself to using the cover display.

Speaking of, that cover display will let you get a lot of work done. That said, many tasks will require you to take a second to open the phone and another second to close it back again. For straight-out-of-the-pocket use, the 5.4” cover display is tangibly smaller than the 6.9” Pro Max display (keep in mind the different aspect ratios). On the flip side, the Duo cover display is only marginally smaller than the 6.3” iPhone 18 Pro display – 88cm² vs 97cm².

We will have more in-depth discussions on the iPhone 18 Pro, 18 Pro Max and iPhone Duo in the weeks to come. There is a small issue, though. The iPhone Pro models will be in stores next week (Friday, September 18), while the iPhone Duo will not be out until late next month (October 23). So, if you do decide to go with an iPhone Duo over an iPhone 18 Pro, you will need patience.

Apple iPhone 18 Pro

These are the best offers from our affiliate partners. We may get a commission from qualifying sales.

256GB 12GB RAM	£ 1,199.00	€ 1,449.00
512GB 12GB RAM	£ 1,399.00	€ 1,629.00
Show all prices

Apple iPhone 18 Pro Max

These are the best offers from our affiliate partners. We may get a commission from qualifying sales.

256GB 12GB RAM	$ 1,549.00	£ 1,299.00
512GB 12GB RAM	£ 1,499.00	€ 1,849.00
Show all prices

Apple iPhone Duo

These are the best offers from our affiliate partners. We may get a commission from qualifying sales.

256GB 12GB RAM	£ 1,999.00	€ 2,299.00
512GB 12GB RAM	£ 2,199.00	€ 2,549.00
Show all prices