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Operator-Reported

AI App That Turns Voice Notes into Clean Text

Voice-to-text app that rewrites messy voice notes into polished text in any style. Solo founder; started in a half-day hackathon. Also profiled on Sta

In plain English

AudioPen lets you ramble into your phone and turns it into clear, tidy writing. You can pick a style, like an email, a list or a social post. It started as a half-day hackathon project by one founder. People pay a yearly or monthly plan to use it without limits.

Automation85%
Startup costNot disclosed
Time to first $Not disclosed
Monthly range*$20,000 Up to

$15K–$20K/mo (founder-reported, Indie Hackers, Feb 2026)

DifficultyMedium
SourceIndie Hackers - AudioPen ↗

Operator: Louis Pereira

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

 OpenAI API ↗
Pay per token

LLM / vision

 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

  1. Pick one daily job (capture, transcribe, convert).
  2. AI does the heavy lifting on device or via API.
  3. Subscription after a free trial.
  4. App Store search + organic short-form content.

What's automated vs. the human 15%

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

Voice-to-text app that rewrites messy voice notes into polished text in any style. Solo founder; started in a half-day hackathon. Also profiled on Starter Story.

Operator: Louis Pereira. Website: https://audiopen.ai/

Estimated split: about 85% of the work automated, 15% human.

Realistic income

Louis Pereira told Indie Hackers AudioPen generates between $15K and $20K per month (Feb 2026). This figure is operator-reported and 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

  • Platform fees and review rules.
  • Big apps may add the same feature.
  • 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.

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