MediumMobile AppLocalClear niche and buyerA computer or phone that can run the model locallyPayments via RevenueCat

Operator-Reported

iPhone App That Makes Song Mashups With On-Device AI

Two ex-tech-YouTubers built an iPhone app whose own optimized local models split and blend songs into mashups on the phone.

In plain English

Mixy is an iPhone app that blends two songs into one mashup. The AI that separates vocals and beats runs on the phone itself, so there is no paid cloud service for each song. People share their mashups on short-video apps, which brings in new users. The founders say it reached about $20K a month within months.

Automation90%

Startup costNot disclosed

Time to first $Not disclosed

Monthly range*$20,000 /mo

$20K/mo recurring revenue (founders, YC launch post, Nov 2025)

DifficultyMedium

SourceY Combinator launch - Mixy ↗

Operator: Joe Kennedy (CEO) and Jonah Siegle (CTO)

Operator-Reported

A named, real operator ran this and shared results publicly. The figures are their own.

Not disclosed.

The tool stack

RevenueCat ↗

Free up to $2.5k MTR

Mobile subscriptions

Core ML ↗

Free with Xcode

On-device model inference

App Store ↗

$99/yr

iOS distribution

Prices are the vendors' published list prices as researched in Oct 2026 and change often — always check the vendor's pricing page.

Step-by-step setup

Make one fun, shareable result: a mashup in seconds.
Run the audio AI on the phone so each use costs you nothing.
Free to try, subscription to unlock more.
Grow through creators posting mashups on TikTok and Reels.

What's automated vs. the human 10%

The machine does

Core AI generation/analysis
Billing and onboarding

You still do

Product quality and support
Distribution and marketing
Compliance and edge cases

Overview

Two ex-tech-YouTubers built an iPhone app whose own optimized local models split and blend songs into mashups on the phone.

Operator: Joe Kennedy (CEO) and Jonah Siegle (CTO). Website: https://usemixy.com/

Estimated split: about 90% of the work automated, 10% human.

Realistic income

In their November 2025 Y Combinator launch post the founders wrote that Mixy had $20,000 in monthly recurring revenue in October 2025 and that they “optimized our own local models” to run on the phone. This figure is operator-reported, not independently verified. This is one operator’s result, often after months or years of work, and doesn’t predict yours. Check the live source — numbers change.

Risks

The $20K/mo figure is from the founders’ YC launch post.
Music rights: sharing mashups of copyrighted songs can break platform rules.
Trend-driven apps can fade quickly.
Startup cost and time to first dollar are not disclosed.

*Income figures are illustrative ranges based on public pricing and typical outcomes reported by practitioners, not guarantees. Most new online businesses earn little or nothing at first. Not financial, legal or tax advice.