Member-only story

7 things React Native developers need to know about iPhone Duo

13 min readNov 5, 2026

iPhone Duo, Apple’s first foldable iPhone, shipped on 23 October 2026, and it changes a few basics for every React Native app, including where your tab bar lives, how many sizes your screens render at and which parts of the display you’re allowed to draw under. This guide is for Expo and React Native developers who want their app to look and work right on iPhone Duo, and covers the setup I needed to get a simulator running, vertical tabs, <SplitView>, expo-hinge and the new safe areas. Everything here is built on Expo's iPhone Duo guide and Apple's Designing for iPhone Duo guidelines, and I've tested it in the simulator, not on a physical device.

1. Get a Duo simulator running

The Duo simulator didn’t show up for me until I upgraded both the OS and the toolchain to

macOS 27.2 (Golden Gate)
Xcode 27.1

If you’re not a Medium member, you can read the rest free here.

Expo’s guide lists the minimum as Xcode 27.1 with the iOS 27.1 simulator runtime, on Expo SDK 58. If you build on EAS, use the sdk-58 or latest image. (moving)

Xcode 27 also replaces Simulator.app with Device Hub, which gives you a 3D iPhone Duo with adjustable poses and hinge angle. Two gaps to know about…

JavaScript in Plain English

7 things React Native developers need to know about iPhone Duo

1. Get a Duo simulator running

Written by Augustine Ezeh

Published in JavaScript in Plain English

Responses (1)

More from Augustine Ezeh and JavaScript in Plain English

Data structures and algorithms are still worth learning in 2026

One week into a data structures and algorithms course, my answer is yes: it's still worth learning, even with AI writing much of my code.

Instead of JSON, Try These 5 API Response Formats to Speed Up Your API

Binary formats are not a magic switch. But for an endpoint that gets hit thousands of times a minute, the format you choose can matter.

REST Is a Lie We All Agreed to Believe. I Proved It in 300 Lines.

I rebuilt tRPC from scratch in one weekend — no framework, no codegen, no React. What I found broke how I think about APIs forever.

Beginner's Guide to Mobile App Development with React Native

If you’re already comfortable with React, building mobile apps for iOS and Android is a new adventure to put your current React skills to…

Recommended from Medium

Claude Fable 5.2 for UI Design: Better, but at What Cost?

I tested Anthropic’s new flagship AI model against Opus 5.5 on a real product design task. Here’s what I learned about design quality…

7 HTML and CSS Tricks That Can Replace Your JavaScript Workarounds

Build an accordion, dismiss a popover, fix jumping layouts, and submit forms without bypassing validation.

Learn JavaScript design patterns — module, singleton, factory and observer with real examples!

A beginner friendly guide to JavaScript design patterns — module, singleton, factory and observer explained with real world examples!

1,300+ Frontend Interview Questions for 2026: JavaScript, React, Machine Coding and System Design…

The questions that actually show up in coding rounds, machine coding rounds and frontend system design rounds, with a link to solve each…

8 React Native Things That Look Simple but Work Differently Than You Think

Here is the 8 React Native Things That Look Simple but Work Differently Than You Think

5 Cool Things People Are Building with Claude Fable 5.2

Anthropic just released Claude Fable 5.2. Here’s what’s new and what people are already building with it.