Apple's first foldable iPhone is revealing a range of unexpected software capabilities as technology reviewers begin testing the device ahead of its October 23 retail launch.

Beyond its foldable design, the iPhone Duo introduces several features intended to make better use of its larger display, including Edge Light for video calls, an adapted Reachability interface and an intelligent photography tool called Smart Take.

Early testing has also uncovered upcoming Apple Pencil compatibility, although reviewers have identified limitations involving third-party applications and MagSafe charging accessories.

Edge Light turns the foldable display into a FaceTime light

One of the more unusual features discovered on the iPhone Duo is Edge Light, which transforms the edges of its unfolded internal display into a virtual lighting ring during FaceTime calls.

When the device is fully opened, the outer edges of the screen can illuminate to provide additional lighting for the user's face.

The feature is particularly useful during video calls in dimly lit environments, reducing the need for external lighting equipment.

Rather than relying on a separate ring light, users can take advantage of the iPhone Duo's expansive display to improve their appearance on camera.

Edge Light was previously available on certain Apple Silicon-powered Mac computers following its introduction in macOS Tahoe 26.2.

The iPhone Duo is reportedly the first iPhone to support the feature.

Although relatively simple, Edge Light illustrates how Apple is adapting familiar software capabilities to the foldable device's larger screen.

Reachability redesigned for a wider screen

When unfolded, the iPhone Duo offers a display approaching the size of an iPad mini.

The additional screen space benefits reading, productivity and multitasking, but it also makes one-handed operation more difficult.

To address this challenge, Apple has developed a horizontal version of Reachability specifically for the foldable device.

Originally introduced in 2014, Reachability allows iPhone users to bring controls near the top of the screen within easier reach by moving the interface downward.

On the iPhone Duo, the feature has reportedly been adapted to accommodate the wider display.

Instead of simply lowering the interface, users will be able to swipe toward the left or right edge to shift parts of the interface in that direction.

This should make controls located farther from the user's thumb easier to access without requiring a change in grip.

According to Wired, Apple plans to introduce the redesigned Reachability feature for iPhone Duo later in 2026.

If implemented effectively, it could become one of the most practical improvements for users who frequently interact with the device's unfolded display.

Smart Take automatically captures the right moment

Apple has also introduced a photography feature called Smart Take, designed to simplify the process of taking pictures.

According to early descriptions, the iPhone Duo can recognize when people in the frame are ready and automatically capture a photograph.

The feature could be particularly useful for group pictures, where coordinating everyone and timing the shutter can be challenging.

Instead of relying on a countdown timer or manually pressing the shutter button, users could allow the device to identify an appropriate moment to take the picture.

Another useful capability involves the iPhone Duo's external display, which can function as a live camera viewfinder.

This allows users to preview the composition on the outer screen while taking photographs, offering additional flexibility when using the foldable device's cameras.

The arrangement takes advantage of the phone's dual-screen design and could make certain photography scenarios more convenient.

Apple Pencil support coming with iOS 27.2

Another notable discovery is the iPhone Duo's planned compatibility with Apple Pencil.

Evidence of the feature appeared in the iOS 27.2 Release Candidate issued on October 20.

According to the report, Apple Pencil support will be enabled through the upcoming iOS 27.2 software update.

The addition could expand the iPhone Duo's usefulness for handwriting, note-taking, sketching and content editing.

With its larger internal display, the foldable iPhone may be better suited to stylus-based activities than conventional smartphones.

Apple Pencil compatibility would also represent a significant expansion of the iPhone's input capabilities, which have traditionally focused on touch interaction.

Third-party apps still struggle with the foldable display

Despite the new features, early reviews suggest that the iPhone Duo's software experience is not yet entirely polished.

One of the most significant concerns involves applications developed by third parties.

According to Engadget, several apps fail to make full use of the phone's internal display when unfolded.

Instead of adapting their layouts to the wider screen, some applications display content only in the center, leaving substantial black areas on both sides.

This reduces the practical benefits of the larger display and creates an inconsistent experience when switching between applications.

However, the problem does not affect every app.

Some developers, including Slack, have already optimized their software to work more effectively with the iPhone Duo's screen dimensions.

Compatibility is expected to improve as developers update their applications and Apple continues refining iOS.

Unlike hardware limitations, many of these software issues can potentially be addressed through future updates.

MagSafe charging presents an unexpected problem

Early testing has also revealed a potential hardware-related inconvenience involving MagSafe charging stands.

Technology reviewer Arun Maini observed that some desktop MagSafe chargers can cause the iPhone Duo to tilt or rotate when the device is fully unfolded.

The issue appears to stem from the way the foldable phone's weight and dimensions interact with the magnetic charging mount.

As a result, keeping the device stable on certain charging stands may be difficult when its internal display is open.

Unlike application compatibility problems, this limitation may be harder to resolve through software updates alone.

However, MagSafe is not the iPhone Duo's only charging option.

Users can continue charging the device through its USB-C port, avoiding the stability issues associated with some wireless charging accessories.

The early findings suggest that Apple's first foldable iPhone offers more than a new physical design.

Features such as Edge Light, Smart Take, redesigned Reachability and Apple Pencil compatibility demonstrate how the company is adapting the iPhone experience to a larger, flexible display.

At the same time, app optimization problems and charging accessory limitations highlight the challenges of introducing a new form factor.

With the iPhone Duo set to reach consumers on October 23, its long-term appeal will depend not only on its innovative features but also on how quickly Apple and third-party developers address these early shortcomings.

Hai Phong