Apple’s iPhone Duo and iPhone 18 Pro may belong to the same flagship family, but they offer very different experiences. One is the company’s first foldable iPhone, combining a smartphone and tablet in a single device. The other sticks to the familiar smartphone design while delivering stronger cameras and a significantly lower price.
The iPhone Duo brings two displays, stylus support and a larger screen for multitasking. However, it comes with compromises, including weaker cameras and the absence of Face ID. The iPhone 18 Pro offers a more conventional experience, with better photography capabilities and familiar features, but lacks the Duo’s versatility.
Both devices were announced in September 2026. The iPhone 18 Pro went on sale shortly afterwards, while the iPhone Duo became available on October 23. Both are now available in many markets.
Specifications at a glance
| Feature | iPhone Duo | iPhone 18 Pro |
|---|---|---|
| Dimensions | 117.8 x 84.1 x 11.3mm folded; 117.8 x 164.6 x 5.2mm unfolded | 150 x 71.9 x 8.8mm |
| Weight | 254g | 211g |
| Display | 7.6-inch foldable OLED and 5.4-inch cover OLED | 6.3-inch OLED |
| Refresh rate | 1–120Hz | 1–120Hz |
| Peak brightness | 3,000 nits | 3,000 nits |
| Processor | A20 Pro | A20 Pro |
| RAM | 12GB | 12GB |
| Rear cameras | 48MP main, 48MP ultra-wide | 48MP main, 48MP ultra-wide, 48MP telephoto |
| Front cameras | 12MP cover, 4MP under-display | 18MP |
| Battery | 4,883mAh | 4,288mAh eSIM-only / 4,056mAh physical SIM |
| Charging | 50% in 20 minutes | 50% in 15 minutes |
| Storage | 256GB, 512GB, 1TB, 2TB | 256GB, 512GB, 1TB, 2TB |
Price and availability
The iPhone Duo is considerably more expensive than the iPhone 18 Pro, reflecting its foldable design and dual-screen functionality.
The Duo starts at $1,999 / £1,999 / AU$3,499 for the 256GB model. The 512GB version costs $2,199 / £2,199 / AU$3,899, while the 1TB model is priced at $2,599 / £2,599 / AU$4,699. At the top of the range, the 2TB version costs $3,199 / £3,199 / AU$5,899.
The iPhone 18 Pro starts at $1,199 / £1,199 / AU$2,099 for 256GB. Its 512GB model costs $1,399 / £1,399 / AU$2,499, the 1TB version is $1,799 / £1,799 / AU$3,299, and the 2TB model comes in at $2,399 / £2,399 / AU$4,499.
That means the Duo costs approximately $800 / £800 / AU$1,400 more at entry level. For that additional money, buyers get a device that can function as both a phone and a small tablet. However, the price difference is substantial enough to make the iPhone 18 Pro a more accessible option.
The iPhone Duo (Image credit: Lance Ulanoff / Future)
Design: Foldable innovation versus familiar styling
The iPhone Duo stands apart from Apple’s traditional smartphone designs. When folded, it has a short, passport-like shape rather than the elongated appearance of the iPhone 18 Pro. It measures 117.8 x 84.1 x 11.3mm when closed and expands to 117.8 x 164.6 x 5.2mm when unfolded.
The iPhone 18 Pro, by comparison, measures 150 x 71.9 x 8.8mm. It is also lighter, weighing 211g compared with the Duo’s 254g.
Their camera layouts are another noticeable difference. The Duo features a punch-hole selfie camera on its cover screen and an under-display camera on its inner screen. The iPhone 18 Pro uses a Dynamic Island cut-out, which accommodates Face ID — a feature missing from the foldable model.
On the rear, the Duo has two horizontally arranged cameras, while the Pro features Apple’s larger triple-camera plateau.
The devices also have different finishes. The Duo comes with a titanium frame and glass back, in Night Sky and Star White. The iPhone 18 Pro combines an aluminium frame with metal and glass on the rear, and is available in Black, Silver, Glacier and Burgundy.
Both phones carry an IP68 rating for dust and water resistance. They also feature Ceramic Shield 2 on the front and Ceramic Shield on the back. However, the Duo’s folding screen and hinge introduce additional durability considerations.
Apple told TechRadar that the widely discussed screen-cracking problem affected only a “small number of units” at launch.
The Duo also takes some getting used to. Its volume buttons, for example, sit on the top rather than the side. The iPhone 18 Pro offers a more familiar design, while the foldable model requires users to adjust to its different form factor.
Despite their differences, both devices received praise for their design. TechRadar described the Duo as beautifully designed and engineered, while its iPhone 18 Pro review highlighted the phone’s attractive new colours.
The iPhone Duo (Image credit: Lance Ulanoff / Future)
Display: The Duo offers two screens
The display is arguably the biggest reason to consider the iPhone Duo. Its main screen is a 7.6-inch, 1878 x 2670 LTPO Super Retina XDR OLED panel, with a 120Hz refresh rate, 430 pixels per inch and peak brightness of 3,000 nits.
Its 1.4:1 aspect ratio provides room for two apps to run side by side, making it useful for multitasking, gaming and viewing content on a larger canvas. However, much of the video available on platforms such as YouTube and Netflix remains in the 16:9 format.
Apple has also added a nano-texture coating to the inner display. This helps reduce glare and makes the foldable crease difficult to notice when looking directly at the screen. The crease can still be seen from certain angles, but it is less distracting during everyday use.
The Duo’s external display measures 5.4 inches and uses a 1398 x 2034 LTPO Super Retina XDR OLED panel. It supports a 120Hz refresh rate, reaches 3,000 nits of peak brightness and delivers approximately 460 pixels per inch.
The iPhone 18 Pro has a single 6.3-inch, 1206 x 2622 LTPO Super Retina XDR OLED display. It also supports a 120Hz refresh rate, reaches 3,000 nits and offers around 460 pixels per inch.
Both phones deliver bright, sharp and smooth visuals. The Duo, however, offers more flexibility through its two-screen design. Its inner display also supports the Apple Pencil, giving it an advantage for users who want to write, draw or take notes directly on their phone.
Cameras: The iPhone 18 Pro has the advantage
Although the iPhone Duo offers a more versatile display setup, the iPhone 18 Pro is the stronger photography device.
The Duo has two rear cameras: a 48MP f/1.6 main sensor and a 48MP f/2.2 ultra-wide camera with a 120-degree field of view. For selfies, it offers a 12MP f/2.2 camera on the cover screen and a 4MP f/1.8 under-display camera on the inner screen.
The iPhone 18 Pro has a more advanced triple-camera system. Its main camera is a 48MP variable-aperture sensor that switches between f/1.5 and f/4.0. It is joined by a 48MP ultra-wide camera and a 48MP f/2.8 telephoto lens capable of 4x optical zoom.
The Pro also has a higher-resolution 18MP f/1.9 front-facing camera.
This gives the iPhone 18 Pro greater photographic flexibility, particularly when shooting distant subjects or taking advantage of optical zoom. Its main camera also offers more versatility through its variable aperture.
The Duo is still capable of producing good photographs. Its two 48MP rear cameras were praised in TechRadar’s review, along with its above-average Center Stage selfie camera. However, it cannot match the Pro’s combination of detail, low-light performance and zoom capabilities.
For anyone who places photography high on their list of priorities, the iPhone 18 Pro offers the more comprehensive camera package.
(Image credit: Future)
Performance and software
Under the hood, the iPhone Duo and iPhone 18 Pro are closely matched. Both use Apple’s A20 Pro chipset, 12GB of RAM and a vapor chamber cooling system.
Their performance is therefore expected to be broadly comparable. TechRadar’s reviews described the Duo as delivering smooth performance, while the iPhone 18 Pro was praised for being fast and efficient.
The Duo does have an advantage when it comes to how users interact with apps and games. Its larger internal display provides more room for gaming, while its split-screen functionality allows two applications to run alongside each other.
The iPhone 18 Pro does not offer the same multitasking experience because of its single-screen design. However, that does not mean it is less powerful.
Software versions differ slightly out of the box. The Duo ships with iOS 27.1, while the iPhone 18 Pro comes with iOS 27. Both can be updated to iOS 27.2, and they are expected to receive software support for a similar period.
Apple has made some adjustments to take advantage of the Duo’s foldable design. Its cover screen, for example, features a status bar and a side-positioned dock intended to make navigation easier. However, these elements can sometimes take up valuable screen space.
App optimisation is another consideration. Apple’s own Mail and Safari apps work well on the Duo, but some third-party applications, including LinkedIn and Instagram, were found to be less polished on its unusual display sizes.
Developers are expected to improve compatibility through future updates, but early buyers may encounter some inconsistencies.
Battery life and charging
The iPhone Duo has a 4,883mAh battery, compared with the iPhone 18 Pro’s 4,288mAh capacity in eSIM-only models and 4,056mAh in physical-SIM versions.
Although the Duo has the larger battery, its foldable screen can consume more power. Apple estimates up to 44 hours of video playback when using the outer display, dropping to 31 hours when using the inner screen.
The iPhone 18 Pro is rated for up to 34 hours of video playback.
For typical use, the difference is much smaller. Apple estimates 24 hours for the Duo and 23 hours for the Pro. TechRadar’s testing also found that the Duo provides solid all-day battery life, while the iPhone 18 Pro delivers outstanding endurance.
Charging is slightly faster on the Pro. With a 60W or higher wired charger, the iPhone 18 Pro can reach 50% in approximately 15 minutes. The Duo takes around 20 minutes to reach the same level.
Both phones can reach 50% charge in about 30 minutes using a 35W or higher MagSafe charger.
Verdict: Which iPhone should you choose?
The iPhone Duo and iPhone 18 Pro represent two very different approaches to Apple’s flagship smartphone experience.
The Duo is designed for people who want more than a conventional phone. Its foldable 7.6-inch display, separate cover screen, stylus support and larger battery make it a versatile device for entertainment, productivity and multitasking. It also manages to combine phone and tablet experiences in a single, pocketable product.
However, that flexibility comes at a significant cost. The Duo is much more expensive, heavier and thicker when folded. It also lacks Face ID and has a less capable camera system than the iPhone 18 Pro.
The iPhone 18 Pro offers a more familiar experience, with better cameras, Face ID and faster wired charging. It also delivers comparable processing power and a high-quality display, while costing considerably less.
For buyers who mainly want a powerful smartphone with excellent photography capabilities, the iPhone 18 Pro covers the essentials. Those who want a larger screen, stylus support and the convenience of carrying a phone and tablet in one device may find the Duo’s additional features worth considering.
At the Duo’s price, another option is to purchase the iPhone 18 Pro alongside an iPad mini. That combination could provide a similar division between smartphone and tablet use, although it means carrying two separate devices.
The Duo is more compact than carrying an iPad alongside a phone, and TechRadar awarded it 4.5 stars in its review. Ultimately, the choice comes down to whether its foldable design and additional screen space justify the considerable premium.
