Starter Story

Founder of a $160K/month fitness app reveals his entire tech stack: Claude with MCPs, PostHog, Superwall, Whisperflow, Notion, and Slack. Mauro is 23. He launched Symmetry a year ago and it’s now doing $160K/month with $3M in revenue across iOS and Android, dominating the Spanish gym app market.

Ken spent nearly his entire career in big tech before to build a mobile app. In his first year since he launched, he hit his $10K/month goal, and grew the game to $155K in revenue with zero paid marketing. This video is the story of why he left a comfortable job to build a game, and how he grew it on his own. *Free database: 100+ Solopreneurs making $1M/year* https://clickhubspot.com/1k92 Say hi to Ken: https://www.linkedin.com/in/kennethylaw/ Check out Harpagia: https://kayelleapps.com/ 🔔 Follow the Second Channel: @StarterStoryBuild 🏁 We're hiring: starterstory.com/jobs Chapters: 0:00 - the $10K game 0:54 - Gus is hosting! 1:10 - What’s your story? 1:48 - Business breakdown 2:24 - Revenue overview 3:39 - Founder background 4:34 - Successful solo devs 5:23 - Quitting tech backstory 6:33 - App timeline 7:38 - Growth and marketing 9:27 - The opportunity in games 10:45 - App demo 11:41 - Tech stack 12:28 - Final advice 13:25 - Gus reflections This video is an educational case study of this founder’s experience. It is not financial advice and does not guarantee any income or results. Every business is different and your results may vary.

Most creators chase trends. Roman chases patterns. He built Career Hound, a boring job board, into a $25K/month business using the same content playbook for two years straight. His framework: Timely content = trend now, dead in a week Timeless content = formats people always want (ex: “companies hiring remote worldwide”) “Content thrifting” = scroll for hours across TikTok, Reddit, IG (video AND text), collect anything that grabs you Spot the patterns others miss, then run that format over and over

Meet Piotr, a solo dev in Poland who built Visualizee, an AI rendering tool for architects and interior designers. He runs the whole thing on nights and weekends while working a full-time job. Here’s the entire stack behind a $10K/month side project: Cursor + Claude Code for building Fal AI for GPU / image generation Supabase for database, auth, and storage Next.js on Vercel for hosting Stripe for payments (subscriptions from day one) Mailerlite for email automation Ahrefs + MonitorMySEO for SEO PostHog, Google Analytics, and Sentry for tracking

22 years old. $160K/month. One year in. But the app isn’t the secret, it’s how he decides what to build. Meet Mauro. He built Symmetry, a gym tracking app that’s now one of the biggest names in the Spanish fitness market. He went through 3 phases: Phase 1: build what we wanted. Terrible. Phase 2: build what users asked for. Mediocre. Phase 3: treat every feature like a science experiment. $160K/month. His system: Set ambitious quarterly OKRs (easier to move metrics when you’re new) Track downloads, activation, retention, ARPU Start from a problem, not a solution Write hypotheses, then A/B test everything for 2+ weeks Kill what doesn’t move the needle, double down on what does One example: adding a single screen at the end of a workout increased retention by 3%. Meanwhile two full redesigns of the home screen moved nothing.