PrintCash with AI
MediumMobile AppLocalClear niche and buyerA computer or phone that can run the model locallyPayments via Stripe
Operator-Reported

On-Device AI Email Cleanup for iPhone

AI email cleanup that never leaves your phone

In plain English

MailBroom is an iPhone app that sorts a cluttered inbox into junk, mailing lists and mail worth keeping. The sorting runs on the phone itself, so your emails never go to a server. Users pay inside the app. The founder built it to clear his own 50,000-email inbox.

Automation90%
Startup costNot disclosed
Time to first $Not disclosed
Monthly range*$460 /mo

$460/mo operator-reported revenue (Indie Hackers product page, Oct 29, 2026)

DifficultyMedium
SourceIndie Hackers - MailBroom ↗

Operator: Aiert

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

  1. Solve one everyday job with a model that runs on the phone itself.
  2. Keep it private and offline: no upload, no per-use model bill.
  3. Free tier with a subscription or one-time unlock.
  4. Grow through App Store search and short demos.

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

AI email cleanup that never leaves your phone. I built MailBroom after getting fed up with my own 50,000-email inbox. It’s an iOS app that uses on-device AI to figure out what’s safe to bulk-delete, worth unsubscribing from, or worth keeping.

Operator: Aiert. Website: https://ios.mailbroom.app/

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

Realistic income

The founder reports $460 per month in revenue on their Indie Hackers product page (checked Oct 29, 2026). This figure is self-reported and not verified by Stripe or any third party. 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

  • Apple/Google can ship the same feature built in.
  • On-device models are limited by phone hardware.
  • 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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