Apple’s iPhone Duo, the company’s first foldable iPhone, can run two apps side by side—but the split is fixed at 50/50 and cannot be resized like Split View on iPad.
Apple’s marketing highlights app pairs and side-by-side windows but says nothing about adjusting the divider. The limitation appears to stem from the device’s display geometry: both the inner and outer displays use a 1:1.4 aspect ratio, and each half of the inner display roughly matches the size and shape of the outer screen. An even split therefore gives each app a canvas it already supports, with the divider sitting on the fold.
Why iPhone Duo doesn’t offer resizable Split View
If users could drag the boundary, it would create intermediate sizes that wouldn’t map neatly to the outer display and would complicate app support. That mismatch would also make it harder for developers to adapt their iPhone apps to every possible split. Based on Apple’s promo videos, the only notable exception is when playing a TV show or movie above another app in portrait: Apple TV content appears in its proper aspect ratio while the lower app is allowed to rise above the fold.
Despite the lack of resizing, the iPhone Duo’s foldable screen offers several multitasking benefits. You can quickly swap between apps, open two windows of the same app, carry on a Messages conversation while viewing another app’s content in both landscape and portrait, and save app pairs to return to later. A social post from @planetofgori on September 10, 2026 states: “So unfortunately, you can’t change the app size when you use split view on the iPhone Duo. Only 1:1. 画面分割した際のアプリサイズは変えられない仕様です🥲”.
Apple’s first foldable iPhone brings a new workflow that differs from the iPad experience—particularly for users accustomed to resizing Split View. The iPhone Duo starts at $1,999; pre-orders begin Friday, October 16, and availability starts Friday, October 23.
