iPhone Duo Review Faults Right-Side Controls, Limited Multitasking and Left-Half Charging Port

The review describes a new application layout system for the Duo. To save vertical space, Apple moved many controls that normally sit at the top and bottom of the screen, such as back buttons and toolbars, into a vertical Control Area on the right side of the display. The main content stays on the left and automatically avoids that area. In most situations, the review says, the two zones are clearly separated.

On the D-shaped outer screen, the review argues, this makes an already asymmetrical display more imbalanced. Clock, cards and notifications that users expect to be centered are pushed to the left content area, and the home screen, apps and other scenes continue the asymmetry. The author says this may require users to adapt, but that the changes affect more than visual balance.

The review says the layout also disrupts interaction habits. On iPhone, users often rely on a shared design language: title bars at the top, navigation at the bottom, back gestures on the left and more menus on the right. On the Duo, buttons from different positions and levels are moved into the right-side Control Area. Because horizontal space there is limited, some buttons that used to combine an icon with a title, including bottom navigation items, are reduced to icons alone. The review says this can make custom or less common functions in third-party apps harder to identify, raising the risk of mis-taps and increasing the learning cost for users.

The article also questions the space savings. Apple moved controls to the side to free vertical height, but the right-side Control Area remains reserved even when a page has few or no controls. The review says the folded Duo is about 1.16 times as wide as an iPhone 18 Pro, yet in most apps its effective horizontal content width is only 0.94 times that of the iPhone 18 Pro. Only some immersive scenes, such as photos, videos or layouts that support horizontal swiping, can use the full screen. On the inner screen, the review says, the left-leaning layout and visual imbalance persist.

Liquid Glass, Apple's design language, also suffers, according to the review. Liquid Glass uses translucent materials and floating controls so content can extend behind the controls; the content then acts as an ambient light source and gives the glass its refraction, blur and depth. On the Duo, the review says, many Liquid Glass buttons are separated from the content and placed in a blank side area. That, it argues, rebuilds the wall between content and controls that Liquid Glass had removed, leaving the glass without rich background material and reducing its visual effect.

The review speculates about why Apple chose this design. It says hardware decisions such as internal structure, screen, hinge and component stacking are often locked earlier than software design. If the Duo's screen ratio and outer display shape were already fixed, the UX team may have faced the question of how to make a determined D-shaped screen look intentional. The review compares this to Dynamic Island: an asymmetry from hardware is turned into a dedicated software interaction model, which then gives the hardware form a functional rationale.

Multitasking is another weak point, the review says. Apple has advanced multitasking on iPad and Mac, including Split View, Slide Over, Stage Manager and free windows. On the Duo, the review says, Apple offers only basic Split View. It does not support split view on the outer screen, top-and-bottom split view, or adjustable split ratios, and the review says Apple did not mention Stage Manager or free windows. Compared with Android folding phones, the review calls the offering conservative.

The review also examines hardware details. It says the outer front camera sits near the top right of the screen, while the inner under-display camera is at the top center of the right screen, a strange combination. The inner FaceTime camera's image quality is not usable, according to media tests cited in the review, and its under-display design does not fully hide it; it can be visible from some angles. The review suggests moving the inner camera farther to the right edge, where it could become the background of a new side status bar. For the outer screen, it suggests keeping the camera centered and returning to a more symmetrical outline, with apps centered, status bar buttons back at the top and Liquid Glass immersive again.

The charging port is also questioned. The review says the iPhone Duo appears to be the industry's first folding phone with the charging port on the left half, while other left-right folding phones place it on the right half. When a cable is plugged in on the left screen, opening and closing the phone makes the cable swing. The review contrasts this with Apple's software animation for opening and closing, which carefully keeps the UI visually seamless. The physical cable, it says, breaks the spatial consistency that the software tries to create.

Still, the review praises the Duo's opening and closing animation. It says the animation is finely made and is the part that most conveys Apple Design, giving the software experience a necessary degree of polish when other feature innovations are limited.