PrintCash with AI
MediumMobile AppFrontierClear niche and buyerAI model/API accessPayments via Stripe
Operator-Reported

AI Personal Trainer App for Strength Training

AI workout generation app; 70,000+ subscribers; grew from 3 founders to 13–14 people; about a third of revenue spent on ads.

In plain English

Gravl is a phone app that works like a personal trainer for the gym. It builds workouts for you and adjusts them as you get stronger. Users pay a subscription instead of paying a human trainer. It has more than 70,000 subscribers.

Automation80%
Startup costNot disclosed
Time to first $Not disclosed
Monthly range*$440,000

$440K+ last month with 70,000+ subscribers (founder-reported on Starter Story, Nov 2025)

DifficultyMedium
SourceStarter Story via Rosetta - Gravl (Julian Gargicevich) ↗

Operator: Julian Gargicevich

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. Generate personal training plans with AI.
  2. Track progress with the phone camera.
  3. Subscription paywall after a free plan.
  4. Grow through players, coaches and short videos.

What's automated vs. the human 20%

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 workout generation app; 70,000+ subscribers; grew from 3 founders to 13–14 people; about a third of revenue spent on ads.

Operator: Julian Gargicevich. Website: https://gravl.ai/

Estimated split: about 80% of the work automated, 20% human.

Realistic income

Julian Gargicevich said on Starter Story: “now we have over 70,000 subscribers. Last month we made over 440K” (Nov 2025). About a third of revenue goes to ads. 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

  • Accuracy of camera tracking.
  • Seasonal usage and churn.
  • 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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