John Ternus Reveals the Exact Moment He Approved the iPhone Duo

In an interview with Tom’s Guide, Apple CEO John Ternus and SVP of Worldwide Marketing Greg Joswiak detailed the engineering decisions that delayed the iPhone Duo’s release, and the single breakthrough that convinced the leadership to move forward.

According to Ternus, Apple never intended to chase market trends or rush a device into production simply to match competitor timelines. The executive team maintained that any foldable hardware had to meet strict standards for durability, display quality, and seamless hardware-software integration.

The primary roadblock for years was the visible crease and structural weakness typical of early flexible screens, issues that Apple felt compromised the user experience. The defining turning point came when Apple’s engineering team applied nano-texture display technology to the foldable prototype.

Originally introduced on high-end hardware like the Mac Studio Display and later brought to the iPad Pro, nano-texture glass uses a matte finish to scatter light and reduce glare. When applied to the iPhone Duo’s flexible screen, the material dramatically reduced reflections and rendered the inner crease virtually invisible to the eye and smooth to the touch.

Ternus recalled that seeing the nano-texture glass integrated into the foldable prototype was the “a-ha” moment for executive leadership. Once the team realized the technology eliminated the glare and visual crease that plagued traditional foldables, the project moved into active production.

The resulting device features a passport-style layout that opens to reveal a 7.6-inch main inner display. Alongside the structural changes, Apple adapted its software ecosystem to fit the new form factor. The iPhone Duo runs on iOS 27, which introduces tailored multitasking capabilities, deep app optimization, and dedicated support for the Apple Pencil. The device also carries an IP68 rating for water and dust resistance.

As the iPhone Duo prepares to hit store shelves this October, the company is betting that a crease-free screen paired with polished software will justify the long wait for long-time iOS users.