The iPhone Duo has two displays: a 7.6-inch folding inner display at 1878 by 2670 pixels and 430 ppi, and a 5.4-inch outer display at 1398 by 2034 pixels and 460 ppi. Both are Super Retina XDR OLED panels with ProMotion up to 120Hz, Always-On and 3000 nits peak outdoor brightness, according to Apple’s tech specs.
Both figures come in under the pre-event reporting of a 7.8-inch inner and 5.5-inch outer display that our iPhone Duo preview relayed. Apple’s own comparison points are different ones: the inner display is 50 percent larger than the iPhone 18 Pro Max’s, and the outer display has more than 90 percent of the screen area of the iPhone 18 Pro.
iPhone Duo inner vs outer display specs
| Spec | Inner display | Outer display |
|---|---|---|
| Size | 7.6-inch | 5.4-inch |
| Resolution | 1878 by 2670 pixels | 1398 by 2034 pixels |
| Pixel density | 430 ppi | 460 ppi |
| Panel | Super Retina XDR OLED, folding | Super Retina XDR OLED |
| Refresh rate | ProMotion up to 120Hz, Always-On | ProMotion up to 120Hz, Always-On |
| Brightness | 1000 nits typical, 1600 nits HDR, 3000 nits outdoor | 1000 nits typical, 1600 nits HDR, 3000 nits outdoor |
| Contrast | 2,000,000:1 | 2,000,000:1 |
| Surface | Custom polymer over glass layers, nano-texture, scratch-resistant coating | Ceramic Shield 2 |
| Camera | Under-display FaceTime camera, f/1.8 | 12MP Center Stage camera, f/2.2 |
The 7.6-inch inner display: crease, finish and shape
Apple calls the inner panel the largest, thinnest iPhone display ever. Its cover is a custom polymer that Apple says has 40 percent higher stiffness than the industry standard, laid over high-strength glass layers and finished with a scratch-resistant coating.
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The nano-texture finish is the part most owners will notice. Apple says it reduces glare and minimizes the visible crease, though Apple has not published a crease depth or a hinge cycle rating. Open, the Duo takes what Apple describes as a wide, passport-like format, and both displays share the same aspect ratio.
Apple’s 50 percent figure is against the 6.9-inch iPhone 18 Pro Max, the largest slab iPhone in the iPhone 18 Pro lineup. The diagonals differ by only 0.7 inches, so the figure is best read as screen area rather than diagonal.
The 5.4-inch outer display: a full phone when closed
The outer display is where the Duo spends its closed time, and Apple’s framing is that it gives up little: more than 90 percent of the screen area of the 6.3-inch iPhone 18 Pro, at a higher 460 ppi than the inner panel. It sits under Ceramic Shield 2, which Apple says has three times the scratch resistance of the previous generation.
The outer display also does camera duty. The 12MP Center Stage front camera lives here, and the Duo-only Smart Take, Duo Preview, Kid Cue and Duo FaceTime features all use the outer screen to show the subject what the rear cameras see.
What drives both displays
- A custom display engine in the A20 Pro drives both displays at once, per keynote coverage
- iOS 27.1 adds Split View for two apps side by side, an upgraded StandBy and a redesigned Dynamic Island
- Layouts adapt to open, closed and posed positions: StandBy, landscape, portrait, seated and standing
- Apple Pencil (USB-C) works on both displays once support arrives later in 2026
Apple has not published the inner display’s thickness, the crease measurement or the hinge’s rated fold count. The iPhone Duo goes on sale October 23, with pre-orders from October 16 at 5 a.m. PT.
