From Hacker House to $2 Million: How Two 18-Year-Olds Built a Million-Download Calorie Counting App
From Hacker House to $2 Million: How Two 18-Year-Olds Built a Million-Download Calorie Counting App
In the fast-paced world of tech startups, where overnight successes are often fueled by viral trends and “vibe coding,” the story of Cal AI stands out. This isn’t your typical tale of a Silicon Valley dropout; it’s the story of two 18-year-old high school graduates, Zach Yadegari and Henry Langmack, who built a calorie-counting app that boasts over 5 million downloads and generated over $2 million in revenue in just one month.
A Classic Startup Story, With a Millennial Twist
Launched in May, Cal AI quickly gained traction, achieving a remarkable 30% customer retention rate. While TechCrunch couldn’t independently verify the exact download and revenue figures, the app’s impressive 4.8-star rating on both the Apple App Store (66,000 reviews) and Google Play (nearly 75,000 reviews, over 1 million downloads) speaks volumes about its user satisfaction.
The app’s core functionality is straightforward: users take a picture of their food, and Cal AI uses sophisticated AI models to estimate the calorie and macro counts. While not a unique concept – established players like MyFitnessPal and newer entrants like SnapCalorie already offer similar features – Cal AI leverages the power of large image models from Anthropic and OpenAI, along with retrieval augmented generation (RAG), to enhance accuracy.
The Power of Large Language Models and Open-Source Data
Yadegari and Langmack’s approach is a testament to the rapidly evolving landscape of AI. They cleverly utilized readily available open-source food calorie and image databases from platforms like GitHub, training their models to recognize diverse food items. This data-driven approach, coupled with their strategic use of different AI models for different food types (“We have found that different models are better with different foods,” Yadegari explains), contributes significantly to Cal AI’s impressive accuracy, estimated at around 90%.
Overcoming Technical Hurdles and Achieving 90% Accuracy
Building Cal AI wasn’t without its challenges. The founders diligently tackled complex technical problems, such as accurately identifying ingredients from cluttered food packages or mixed dishes. Their persistence and innovative approach resulted in an app that’s proving to be highly effective for many dieters.
From Middle School Coding to Multi-Million Dollar App
Yadegari’s journey is particularly inspiring. Unlike many young coders who grew up with AI copilots, he honed his skills in Python and C# during middle school. At just 16, he sold his first business – a website cleverly named “Totally Science” that provided access to unblocked games in schools – for a remarkable $100,000 to FreezeNova, a game company.
This early success, along with watching Y Combinator videos and connecting with the coding community on X (formerly Twitter), fueled his ambition. He met Blake Anderson, a 24-year-old experienced consumer app developer known for creating ChatGPT-powered dating apps, on X, who later joined as a co-founder.
The Hacker House Experience: Lessons Learned
The duo’s decision to move to San Francisco and live in a hacker house while building their prototype is a classic Silicon Valley tale. While the experience was “very fun and taught me a lot,” Yadegari notes, it also led to a surprising realization. Surrounded by older developers, he decided that college was a path he wanted to pursue, defying the stereotypical Silicon Valley dropout narrative.
A Growing Team and Future Plans
Today, Cal AI is more than just Yadegari and Langmack. The team has expanded to include Jake Castillo (COO) and eight full-time employees, covering development, design, and social media management. Their success story is a testament to their hard work, innovation, and the power of collaboration.
Conclusion: A Bright Future Ahead
The story of Cal AI is a remarkable example of how young entrepreneurs, armed with technical skills, innovative ideas, and a willingness to learn, can disrupt established markets. Zach Yadegari and Henry Langmack’s journey is far from over. With their impressive success, commitment to innovation, and a growing team, Cal AI is poised for continued growth and success in the ever-expanding world of health and fitness technology. Their story serves as a powerful inspiration for aspiring young entrepreneurs everywhere, proving that age is just a number when it comes to achieving extraordinary things.
Source: TechCrunch
