Apple's iPhone Duo sidebar limits the 5.4-inch cover display

Apple’s new foldable smartphone, the iPhone Duo, is already facing scrutiny over how its software manages the device’s smaller exterior screen. While the hardware is available to a limited number of buyers, early reports indicate that the operating system restricts the usable area more than competitors in the same category.

Allison Johnson of The Verge noted in a recent review that the iPhone Duo feels harder to operate with one hand than the Samsung Galaxy Z Fold 8. She attributed this difficulty to the physical shape of the devices. The Fold 8 is taller and narrower, which makes its cover screen easier to reach and navigate. For users who chose foldable phones specifically for the utility of the outer display, this ergonomic difference is a major factor.

A specific design choice in the iPhone Duo interface exacerbates the issue. Apple implemented a sidebar intended to simplify navigation. However, this feature places a dock on the right side of the screen, leaving a large portion of the 5.4-inch display empty. Social media users have pointed out this wasted space, noting that the mandatory sidebar consumes a visible chunk of the viewable area.

In contrast, the Galaxy Z Fold 8 leaves most of its cover screen free for main content. Johnson’s video comparison showed that even when the Fold 8 uses a navigation bar instead of gestures, the difference in wasted space is less obvious than on the iPhone Duo. For users who rely on navigation gestures on Samsung devices, the cover screen is nearly fully utilized.

Apple’s approach appears to be a strategy to make a small display function like a traditional slab phone. By shrinking the available space, the system stretches media to appear taller. The Galaxy Z Fold 8 demonstrates that an alternative method, which allows content to occupy the full width of the screen, can be effective.

The iPhone Duo is currently on sale, though stock is limited. Samsung continues to market the Galaxy Z Fold 8 as a successful entry in the wide foldable category. Johnson and other tech journalists are scheduled to discuss these early findings in upcoming segments, providing further context on how the two devices compare in daily use.