Apple announces that more than 100,000 apps are optimized for iPhone Duo, here’s what’s still missing

Apple today announced that more than 100,000 apps have been optimized for the iPhone Duo, which was released two weeks ago. We’ve confirmed that this figure refers to apps built with iOS SDK 27.1 or later, meaning these apps fill the full width of the iPhone Duo’s inner and outer screens and have vertical controls in the status bar.

A statement from Susan Prescott, Apple’s vice president of Worldwide Developer Relations:

It’s wonderful to see how quickly developers have adopted iPhone Duo, and we’re grateful for their creativity and innovation. Today, more than 100,000 apps designed for iPhone Duo are already available in the App Store, and thousands of optimized apps are added to the store every day. In the past month alone, thousands of developers have joined us for workshops in 19 cities around the world to learn about iPhone Duo and deliver updated apps to their users. The enthusiasm has been incredible, and we’re excited to see the pace of updates continue to accelerate as more apps are optimized for iPhone Duo.

Apple said thousands of apps optimized for the iPhone Duo are added to the App Store every day, with recent examples including Microsoft’s Excel, OneNote, PowerPoint and Word apps, as well as Etsy, Goodnotes, Halide Mark III, NBA, NHL and Zoom apps. Other apps optimized for the device include Amazon Prime Video, Fantastical, Flighty, Instagram, MLB, Netflix, SmartGym, WhatsApp, YouTube, and more. There are too many to list.

Apps optimized for iPhone Duo have a “Made for iPhone Duo” badge in their App Store listings on the device, making them easy to identify.

iOS 27.2 added Apple Pencil (USB-C) support to iPhone Duo, allowing users to draw in apps like Procreate Pocket, take notes in Apple Notes, Fineliner, and TypeDraw, and annotate documents in apps like On-Device Preview.

On the other hand, with millions of apps available in the App Store, there are unsurprisingly many apps that are still not optimized for the iPhone Duo, with the following examples listed alphabetically: AMC Theaters, Amazon Fire TV, Apple Store, Best Buy, Bluesky, Delta, DoorDash, Duolingo, Fandango, FedEx, Goodreads, Google Docs, Google Home, Google Sheets, Google Slides, GrubHub, JetBlue, Libby, Microsoft Authenticator, Microsoft. Teams, MTA, Nike, PayPal, PictureThis, Ring, Southwest, Spectrum TV, Starbucks, Steam, Uber Eats, UPS, USPS, Venmo, Verizon, Wells Fargo, Whole Foods and YouTube Music.

Apple said developers can easily optimize their apps for the iPhone Duo. Apps that use standard SwiftUI and UIKit components automatically adapt to each view, with controls moved to the status bar and multi-column support on the internal display. New APIs allow developers to optimize their apps for different device layouts and poses.

Apple has held more than 50 in-person workshops on the iPhone Duo app in 19 cities around the world, and there are online resources such as the Apple Developer Forums.

Meanwhile, apps created with the iOS 27 SDK resize to fill most of the iPhone Duo’s internal screen, but avoid the status bar on the right edge. Apps created with the iOS 26 SDK or earlier run on iPhone Duo, but appear in the center of the inner screen, with lots of empty black space on the left and right sides of the apps.

Optimization of iPhone Duo apps has been a hotly debated topic on social media platforms, with some people pointing out apps that are not yet optimized and others saying the problem is exaggerated. It’s clearly a mixed bag, with some apps optimized and others not. However, more and more apps are being updated every day, so the situation is improving quickly.