Apple’s new iPhone Duo introduces split-screen app pairing on its 7.6-inch foldable display—a first for an iPhone. But if you were hoping for the kind of flexible, drag-to-resize multitasking experience available on the iPad, you’ll be disappointed.
Even Splits Only, No Adjustable Divider
When using two apps side by side on the iPhone Duo’s inner foldable screen, the split is fixed at an even 50-50 division. There’s no option to slide the dividing line and give one app more space than the other. This setup holds even in landscape mode. The reasoning behind this is technical: both the Duo’s inner display and its outer screen share a 1:1.4 aspect ratio, and when opened flat, each half of the inner screen maps closely to the size and shape of the outer display. By enforcing a 50/50 split, Apple ensures that each app is shown in a configuration it already supports—while keeping the fold crease aligned with the division between apps.
iPad’s Split View Versus Duo’s Constraints
On an iPad, users have been able to dynamically resize app windows since the introduction of Split View in iOS 9 back in 2015. That flexibility allows for wide and narrow layouts, depending on multitasking needs. The Duo does not offer this. Not only would adjustable splits result in “in-between” screen sizes that mismatch the outer display, but it would also place extra burden on developers, forcing them to design for many more aspect ratios.
What Duo’s Side-by-Side Mode Does Let You Do
Despite that limitation, the multifunctional capabilities are still a leap forward for iPhones. You can open two different apps side by side, or pair two windows of the same app. This is supported in both portrait and landscape modes. The Duo also adds the ability to save app pairs, so you can return to your two most-used combos instantly.
The iPhone Duo starts at US$1,999. Pre-orders begin on Friday, October 16, with the device going on sale on Friday, October 23. For users switching from an iPad, the difference in multitasking will be one of the sharper adjustments.
What this means for users is that the Duo delivers split-screen multitasking for the first time on an iPhone—but with caveats. If you expect that adjustable, iPad-style flexibility, the Duo doesn’t deliver. Still, this design choice reflects a balancing act: aligning the UI with display hardware and simplifying developer support. Going forward, the question will be whether future iPhones will expand these split-view options—or whether this fixed layout becomes the standard for foldable models.
