He turned a simple idea into a $15K MRR mobile app

Sebastian Rohl had no idea what he was going to build when he quit his job. He gave himself 12 months of runway and started building, but six months in, his app had fewer than a dozen downloads. Then he changed his strategy, found an idea that worked, and within two years was making $15,000 a month as a solo developer on the App Store. His app has been downloaded over 300,000 times.

The failure that changed the strategy

Rohl's early approach was to build apps he thought were cool. He spent months developing a weightlifting tracker with detailed analytics, graphs, and historical data. He launched it and got almost nothing: a handful of downloads, no traction, no revenue. The problem wasn't execution—the app worked fine—it was that nobody was looking for it. He had built something in a vacuum, based on what he assumed people wanted.

The turning point came when he realized he needed to reverse the process. Instead of building first and hoping people showed up, he needed to find what people were already searching for and build that. He started studying the App Store's search data, looking at what terms had high volume but few quality results. This is how he found the idea that eventually became his $15K MRR business.

Finding the signal in search data