Pre-orders for the new iPhone Duo don’t start until later in October, but the device may already have its first killer app. Or at least its most whimsical one! Indie developer Vidit Bhargava has been showing off an app for the first Apple foldable that replicates the experience of using a classic Walkman.

The app, called Duo-Man, takes clever advantage of the Duo’s two screens — a foldable, 7.6-inch inner display when it’s open, and the 5.4-inch outer display when it’s shut closed. The app imitates how walkmans used to function: you can open up the Duo to pick your music and “insert” your cassette tape, then close the device shut to start listening.

Of course, you’re not actually using cassette tapes and players with physical buttons, but Bhargava says he tried to make the experience feel as authentic as possible by recording the button clicks and the static noise from a real Walkman to incorporate into the app, he said.

“I have been a long-term Walkman enthusiast — still own and listen to it occasionally — and have repurposed them in the past,” the developer told TechCrunch. “So, when I was looking for ideas for the hackathon, I was looking for physical objects that have a hinge. I noticed how the Walkman’s door needed to be opened to insert a cassette, and I thought it would be cool to replicate on the Duo,” he said.

While foldable smartphones have been around for years, the iOS developer community tends to be particularly creative, partly thanks to Apple’s App Store ecosystem and its robust tools that let developers build, host, market, and profit from their software. It’s why you often see developers building their apps for iOS first before considering an expansion to Android.

However, the app also taps the broader “retro” trend in tech, as younger consumers seek out classic, physical tech like digital cameras, flip phones, CDs, landlines, and yes, even cassette tapes.

Bhargava initially built the app and demoed it at the Bitrig hackathon this weekend, where it won second place. Bitrig offers software that lets developers use AI to build native apps using Apple’s Swift programming language.

After the developer posted about the Duo-Man on X, it quickly attracted attention, topping 1.8 million views and nearly 10,000 likes. That attention has inspired Bhargava to take what was initially just a fun hackathon project and turn it into a real app.

When it arrives, the app will support Apple Music and local files, and will even include a feature that would let you use your Apple Pencil to “roll” the cassette loop, we’re told. On X, Bhargava also said he plans to make the fast-forward and rewind experiences similar to the original Walkman. Spotify support may be added further down the road.

This is not Bhargava’s first app. The indie developer has published a dictionary and vocab builder, LookUp; a movie recommendations app, Movie Buzz; a time zone utility; and others.