Every app worth opening on both screens of iPhone Duo.
We test, rank, and explain the apps, tools, and settings built for iPhone Duo's fold — plus plain-English tutorials for getting the most out of dual-screen multitasking.
What is iPhone Duo, and why does it need its own app guide?
iPhone Duo is Apple's dual-screen iPhone, built around a hinge that lets two panels fold flat into a single pocketable device or open into two independent workspaces. That hinge changes how software should behave: an app that simply stretches across both panels usually breaks at the seam, while an app designed for the fold can turn the second screen into a real second workspace — a sketch app can keep your reference photos off the canvas, a calendar app can accept a task dragged straight off your to-do list.
Apps for Duo exists because most App Store listings don't tell you which of those two categories an app falls into. We install, test, and write up every app and update with the fold specifically in mind, rank them by how well they actually use the second screen, and publish plain-English tutorials for getting more out of Duo's multitasking, settings, and developer tools. Everything here is independent testing — Apps for Duo is not affiliated with, endorsed by, or sponsored by Apple.
Start here
- Browse the iPhone Duo apps directory
Every app we've tested, ranked by fold quality.
- Read setup guides and reviews
Tutorials, workflows, and hands-on reviews.
- Building for Duo? Start with iOS 27
Our developer guide to the current beta stack.
Editor's picks
Apps that make the most of the fold.
From the Learn hub
Reviews, tutorials, and Duo news.
iOS 27, Xcode 27.1 beta, and macOS Tahoe 26.6: what Duo developers need to know
A practical rundown of the current developer beta stack for iPhone Duo: what's new in iOS 27 for dual-screen apps, what Xcode 27.1 beta requires, and why macOS Tahoe 26.6 matters for your build machine.
Sep 21, 2026
5 Split View workflows worth setting up on your iPhone Duo this week
Most people use a fraction of what iPhone Duo's fixed 50/50 Split View can actually do. Here are five workflows we set up on day one and still use every day.
Sep 18, 2026
DuoSketch review: drawing on iPhone Duo's inner display, one workspace at a time
We spent two weeks sketching and inking using DuoSketch's Split View workflow on iPhone Duo. Here is what it gets right, where it still stumbles, and whether the one-time unlock is worth it.
Sep 18, 2026