20-year-old who earned 38 million won in 30 days with an 'app that shows your brain rotting'
Date
Nov 12, 2025
Classification
- Solo Freelancer / Personal Branding
Solo Business Night
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[Source: brainrot]
Entrepreneur in his 20s with "Zero App Development Experience" Earns 38 Million Won in 30 Days with Just an AI Assistant
🫑 3-Line Summary
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Yoni Smoliya, who had no prior experience in mobile app development, wrote over 90% of the code using AI tools (Cursor, Claude) and launched 'Brainlot,' an app to solve smartphone addiction, in just 2.5 months.
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By sharing our failure process every day for 450 days, we gathered 200,000 followers, and by achieving the #1 ranking on Product Hunt, we generated $26,000 (approximately 38 million KRW) in revenue in the first month of launch without any separate advertising costs.
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See for yourself how we have chosen rapid execution over perfection to practice the "distribute bugs" spirit, and are building sustainable growth by communicating with users through a transparent "Building in Public" strategy.
🥦 Insight
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AI merely assists; the essence is the weapon called 'authenticity'
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Did you think, "Wow, maybe I should whip up an app with AI and make money too?" Let's calm down for a moment and look at the numbers objectively. It took Yoni 2.5 months to build the app, but it took 450 days to gather people to buy it.
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AI has lowered the barrier to entry for development to the lowest level. Now, anyone can become a 'maker.' However, not everyone creates 'products that sell.' In Yoni's success equation, the real variable was not AI, but the authenticity of 'Building in Public,' which showed even the failures without reservation.
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Technology has become easier, but interest has become expensive. You may now need to spend more time building a fanbase to listen to your story than learning to code. Starting today, try documenting your imperfect journey. Those records will become your most powerful marketing budget in the future.
A brain character that changes according to the stages of screen time. The sight of the brain rotting away is both cute and intuitive. It made me chuckle while watching it. 😂 I think I understand why people liked it. [Source: brainrot]
— View original —
Hello! This is Solo Business Night. 💫
The entrepreneur I would like to introduce today is Yoni Smolyar, a 20-something entrepreneur who earned $26,000 (38 million won) in just 30 days after launching an app created with AI.
The app he created, Brainrot, is a screen time mobile app that shows the brain 'rotting' the longer you scroll.
Earlier this year, Yoni was completely addicted to his smartphone. Lost in the dopamine of likes, comments, and followers, he stared at the screen for over 10 hours a day and experienced memory loss and decreased concentration. There were already countless screen time apps available to help him. However, unable to find a solution that suited him, he decided to create one himself!
Yoni is a former software engineer. He had worked on numerous side projects for over five years, but most ended in failure, and he had absolutely no experience in mobile app development. However, thanks to AI coding tools, he was able to complete Brainlot in just 2.5 months! He confessed that he built the app using over 90% VIVE coding. At that time, Yoni had 200,000 followers, accumulated over a little more than a year at the cost of his social media addiction!
The results were amazing. In late May 2025, we recorded thousands of downloads on the first day of launch and achieved $26,000 (approx. 38 million KRW) in revenue within a month. And to this day, we are consistently generating over $10,000 (approx. 14 million KRW) in monthly revenue through BrainLot.
The screen time app market is already saturated, so what was Brainlot's differentiation strategy?
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