The iPhone Duo boasts the biggest display ever on an iPhone, surpassing even the iPhone 18 Pro Max. But what do the two models look like side by side? A hands-on video provides an excellent visual comparison.
Here’s how the iPhone Duo and iPhone 18 Pro Max measure up
If you’re after the largest possible iPhone screen, the iPhone Duo’s folding display delivers exactly that.
But just how much bigger is it than the iPhone 18 Pro Max? And how do they compare in various configurations?
A clip shared on Instagram by @thetechchap gives a clear side-by-side view of both new devices.
As shown, when unfolded the iPhone Duo’s width is almost identical to the iPhone 18 Pro Max’s longest dimension. Here are the figures from Apple’s technical specifications:
| | iPhone Duo | iPhone 18 Pro Max |
| Height | 4.64 inches closed 4.64 inches open | 6.43 inches |
| Width | 3.31 inches closed 6.48 inches open | 3.07 inches |
Apple defines height and width based on typical usage patterns. Since both iPhones can be used in any orientation, it may be more useful to compare height against width and vice versa.
For instance, the iPhone 18 Pro Max’s 6.43-inch height aligns closely with the iPhone Duo’s 6.48-inch width. In a certain orientation, as seen in the video, their lengths are nearly the same.
Of course, the Duo has the advantage of its 4.64-inch height, which is far more spacious than the iPhone 18 Pro Max’s 3.07-inch “width.” And it folds down, making it more compact for carrying and one-handed use.
What do you think of the size differences between the iPhone Duo and iPhone 18 Pro Max? Share your thoughts in the comments.
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