Less than a week after Apple opened preorders for its first foldable smartphone—the iPhone Duo—its official website was already showing delivery dates extending into January 2027 for some orders.
According to TrendForce, initial user feedback has been polarized. While users have praised the split-screen functionality and viewing experience when the device is unfolded, black borders in some apps, button placement, and fingerprint authentication have added to the learning curve.
Reports of damaged displays and high repair estimates have also shifted attention toward product reliability and long-term ownership costs. Given the Duo’s premium positioning, the key question for consumers is whether its expanded screen space delivers a sufficiently compelling overall experience to justify the price.
TrendForce estimates that global foldable smartphone shipments will edge up just 0.5% in 2026. Apple’s first foldable iPhone is expected to ship approximately 5 million units, accounting for about 24.8% of the market in 2026. With the overall market remaining largely flat, Apple’s entry is poised to accelerate shifts in market share among competing brands.
One of the Duo’s defining features is its barely visible display crease. TrendForce explains that a foldable OLED display consists of multiple layers, including cover materials, optical adhesives, display components, and encapsulation structures. These layers experience different tensile, compressive, and shear stresses as the display folds. Managing these stresses requires careful optimization of the bending radius, layer thicknesses, and elastic moduli, while allowing controlled slippage within the display stack through the adhesive layers.
These measures reduce strain on functional layers and improve the display’s recovery when unfolded. Nanoscale surface textures also scatter reflected light, making the reflective band along the fold less noticeable. By addressing structural deformation and optical appearance, respectively, these approaches improve perceived brightness uniformity across the crease.
The Duo’s teardrop hinge plays a critical role in dynamically controlling display support and clearance. When unfolded, the hinge keeps the display flat and provides the stability for touch input. When closed, it creates the space needed for the panel to fold along its intended curvature.
One hypothesis arising from recent teardown analyses of damaged Duo displays is that insufficient retraction of the central support during folding may cause unintended contact and localized stress concentrations. Apple has provided replacements for a small number of devices exhibiting inner-display abnormalities. From an engineering perspective, further improvements would likely center on coordinated control of hinge travel, support height, bonding precision, and assembly tolerances.
The Duo also brings a larger workspace to a portable form factor, allowing users to read documents, review AI-generated summaries, and edit content simultaneously. Translating this additional screen space into meaningful productivity gains requires apps to dynamically adapt their layouts as the device opens and closes, while preserving reading positions, text input, and ongoing tasks. Some apps still display black borders or fail to make full use of the available screen area, indicating that software adaptation has yet to fully capitalize on the hardware’s capabilities.
The larger display also places greater demands on power management. Although lowering the refresh rate can reduce some display-driving power consumption, the power required for OLED light emission still depends on brightness, emitting area, and displayed content. Even a static document with a white background continues to consume power.
Balancing large-screen multitasking, AI processing, and battery life therefore requires a combination of more efficient emissive materials, optimized optical structures, and adaptive display-driving technologies.
TrendForce notes that Apple’s greatest advantage lies in its ability to integrate chips, operating systems, and its developer ecosystem. As app compatibility and hardware reliability improve, the Duo is expected to further expand the practical value of foldable displays, helping shift competition in the foldable smartphone market from form-factor innovation toward multitasking efficiency.