iOS 4 first appeared nearly 10 years ago as Apple’s first mobile operating system to abandon the iPhone OS naming convention. The 18-year-old developer has now lovingly recreated iOS 4 as an iPhone app and it’s a beautiful blast from the past. If you’ve never been able to use iOS 4 or you’re a fan of the iPhone 3G, OldOS almost flawlessly draws on the experience of using the iPhone from a decade ago.
OldOS is “designed to be as close to perfect pixels as possible,” says Zane, the developer behind the app. Everything is built using Apple’s SwiftUI, so it includes oily smooth animations and even the old iPhone home button, which vibrates with haptic feedback to feel like a real button.
Today is the starting day
Introducing OldOS – iOS 4 beautifully rebuilt in SwiftUI.
* Designed to be as close to perfect pixels as possible.
* Fully functional, maybe even usable as a second OS.
* ️ Fully open source for anyone who can learn, modify and upgrade. pic.twitter.com/K0JOE2fEKM
– Zane (@zzanehip) June 9, 2021
The only apps that don’t work as you’d expect are Messages and YouTube. Apple uses YouTube packaging directly in its operating system, and the developer behind OldOS says it “still has some major problems with YouTube” and messages that work to fix them.
Everything else is mostly flawless. and you can even surf the web in the old Safari user interface. The App Store also lists apps that will redirect you to the modern download and installation store. There are some things that just don’t work, including folders and no shaking to rearrange apps on the home screen.
We’ve seen this type of nostalgic app appear on the iPhone before. Rewound launched in the App Store in December 2019, turning the iPhone into an iPod. Apple quickly downloaded the app a few days later, citing store violations.
This latest OldOS app is available in Apple’s TestFlight service, which is typically used to distribute beta versions of apps. That means it probably won’t last long before Apple makes an exception, so take it while you can. Zane also publishes the source code for the entire GitHub project, so if you want to compile it into Xcode, it will live forever.