The foldable iPhone Duo offers a larger display and prestige, but with notable compromises

The iPhone Duo appears incredibly sleek, but incorporating two displays and a hinge into a portable iPhone required Apple to compromise on certain aspects. Apple’s inaugural foldable smartphone, priced from $1,999 to $3,199, features a 7.6-inch inner display when opened, touted by Apple as the ‘largest iPhone display ever.’ This is 50% larger than the display on the upcoming iPhone 18 Pro. Despite costing $700 more than the iPhone 18 Pro Max, the Duo necessitated omitting some hardware and features to accommodate the new mechanical parts inside. Certainly, early adopters will enjoy instant prestige and unique features exclusive to the foldable device, but these benefits come with a price. If you’re deciding between the iPhone Duo and the iPhone 18 Pro, consider these four trade-offs. The camera system is likely the most significant hardware compromise. The Duo’s front-facing camera is 12 megapixels, whereas the iPhone 18 Pro and Pro Max boast an 18-megapixel Center Stage camera with autofocus. Crucially, the Pro models include a dedicated telephoto lens for distant subjects, which the Duo lacks. However, there’s some good news for photographers. The foldable design incorporates a 48-megapixel ultrawide lens ideal for wide landscapes and macro shots, similar to the hardware on the iPhone 18 Pro Max. Additionally, the Duo’s outer screen acts as a viewfinder when the rear cameras are used, a first for iPhone, allowing subjects to see the shot as it’s taken—a feature described on X as ‘boyfriend-friendly.’ In summary, while you get some innovative photo features, you sacrifice some premium camera technology from the iPhone 18 Pro series. If you have a distinctive face, the iPhone Duo won’t recognize it. This device is the first premium iPhone in years to replace Face ID with Touch ID. Instead of unlocking via facial recognition, Duo users will rely on a fingerprint sensor integrated into the side button or their Apple Watch. The iPhone 18 Pro and Pro Max retain Face ID, which uses the front camera system. The Duo does not feature the Action button. This customizable button, found above the volume controls on iPhone 15 and newer models, is absent from the Duo. On the iPhone 18 Pro, the Action button can be configured to silence the phone, launch the camera, start a voice memo, activate a shortcut, or enable focus mode. The Duo, however, only has the standard camera and volume control buttons. Although the Duo has dual batteries, the large inner display consumes more power. Apple states that the phone can stream video for up to 26 hours when unfolded, compared to 38 hours for the iPhone 18 Pro Max. The smaller outer screen provides up to 37 hours of streaming, slightly less than the Pro Max. Additionally, charging is slower; the Duo requires 20 minutes to reach 50% charge with a 60W adapter, while the iPhone 18 Pro Max achieves this in 15 minutes.