The iPhone Duo is the first iPhone that can run two apps side by side, but it does not work like Split View on the iPad. When two apps share the 7.6-inch inner display, the divider between them cannot be dragged, so the split is always 50/50.
Apple’s marketing for the phone talks about app pairs and side-by-side windows, and it says nothing about resizing them. The iPhone Duo goes up for pre-order on October 16 and launches on October 23, and its full spec sheet is in our launch rundown.
The Split Is Fixed at 50/50 on the Inner Display
iPad owners have been able to resize apps in Split View since iOS 9 introduced the feature in 2015. That lets one app take most of the screen while a second sits in a narrow column beside it. On the iPhone Duo, whether you are writing an email, browsing the web or checking social media, each app gets exactly half of the inner display.
Apple has not explained the limit, and two likely reasons stand out.
- Display geometry: the divider lines up with the fold in the middle of the inner display, so a lopsided split would push an app across the crease
- Developer workload: supporting any window width on an iPhone would take far more work from app makers than one fixed ratio, and a fixed ratio lets existing iPhone apps display cleanly
The side-by-side layout described here is for the 7.6-inch inner display, and the phone also has a 5.4-inch outer display. Other quirks of the design are collected in the details Apple did not mention on stage.
Apple Is Already Getting Developers Ready
Apple released the first Xcode 27.1 beta on September 18 with support for iPhone Duo app development, and iOS 27 was expected to be tailored for the foldable, with side-by-side apps and other iPad-like multitasking. The fixed split shows how far that multitasking goes.
Apple’s Craig Federighi has said the iPhone Duo can fill the iPad mini gap, and the fixed split shapes what that looks like in day-to-day use. Software support is also part of the story when comparing the phone with Android foldables, which have offered resizable multitasking for years.
Apple has not said publicly whether resizing could come in a later software update.
What to Know Before Pre-Ordering
- Two apps can run side by side on the 7.6-inch inner display
- The divider cannot be dragged, so neither app can be enlarged
- iPad-style resizing is not available, which matters for anyone hoping the phone can stand in for a tablet
- Pre-orders open on October 16, and shoppers can start looking at the best iPhone Duo cases now
Our Take
A fixed split is easy to understand, and it avoids awkward layouts around the fold, which makes sense for a first foldable. Anyone who expects iPad-style window control will be disappointed, and I would wait to see how much software support the phone gets before treating it as an iPad replacement.
