How I built a $30K/month mobile app | Starter Story

John McAvoy, a self-taught coder from Scotland, built a mobile app that has been downloaded over five million times and now generates roughly $30,000 per month in revenue. The entire project began not with a business plan, but with a personal frustration he wanted to solve for himself. On this episode of Starter Story, host Pat Walls pressed McAvoy on the specific decisions, tradeoffs, and free strategies that turned a side project into a sustainable solo business.

The idea came from a real, narrow problem

McAvoy did not set out to build a startup. He had a specific, annoying problem in his own life and wrote code to fix it. That app, which helps users track and manage a particular kind of recurring personal data, was not designed to be a mass-market product. It was designed to work for one person: him. This constraint turned out to be an advantage. Because the problem was real and concrete, McAvoy did not have to guess at what users wanted. He was his own first customer, and every feature he built was something he actually needed. The app’s utility was genuine, not hypothetical.