This $100M AI App Just Changed Software Forever

It's also one of the top health and fitness apps in Apple's App Store and is projected to generate more than $30 million in revenue this year.

We had just finished 2025 having done $30 million in that year.

In December of 2025, an 18-year-old sold his AI app for what experts say could be over $100 million, changing what we thought about software forever. Before, most startups needed to have a highly trained team of developers and raise thousands with investors just to start. But this 18-year-old built this app with his high school friends, and within a year, they scaled it to over $30 million a year in revenue. So today I'm going to break down exactly how this simple app became a $100 million company, the 3 strategies that actually got it there, and how right now anyone watching this can do the exact same thing. So let's get into it. So Zach started coding when he was 7 years old because he was obsessed with video games and wanted to make his own. His mom put him in a coding camp, and from that point on, he spent years building stuff, little games and projects here and there that went nowhere. But it gave Zach the knowledge he needed to make the right idea work. And the idea came when he wanted to bulk up for the gym and he started tracking calories on MyFitnessPal. But after just 3 days, he quit because of how annoying it was to weigh every meal on a scale and manually type out every single ingredient. To him, every fitness app sucked. And when AI models like ChatGPT started dropping, he saw the opportunity to make something better. And the idea is actually really simple. What if you could just take a picture of your food and get the calories instantly without typing or weighing anything? So he teamed up with a friend he met at coding camp and a 23-year-old founder who had already grown 2 other apps to millions of downloads. Together, they built the first version of Cal AI in about a month and launched it around May of 2024. That first version of the app was dead simple but incredibly useful. You basically just had to press one button to take a picture of your food, and a prompt was sent to an AI model to calculate the calories. And within 3 to 4 months, they hit a million downloads. Then after 6 months, they were generating over $1 million a month in revenue. And just in the beginning of the year, they sold the app to their biggest competitor for multi-millions. Some even say over $100 million. And here's what this means to the AI apps and software space. What Zach did is impressive, but the landscape has completely changed since he started. When Zach built Cal AI, he already knew how to code, and that gave him a real advantage. But the advantage you have right now is that the barrier to building an app is basically gone. When Cal AI launched in 2024, tools like Cursor and Lovable were already making it easier to build software. But now in 2026, we have vibe coding tools where you can literally describe what you want and AI builds the app for you. Even Zach said this.

My friend actually that I went to high school with, he built an app on Rourke. It's called Wrestle AI or Fight AI. He released two and it's now doing $30,000 a month. And he's also just like a normal kid in college.

So you don't need to be a developer to build a million-dollar app anymore because you can use tools like Cloud Code, Cursor, or Replit without knowing how to code. But here's what hasn't changed. The business side is still the hardest part to make this work and is still 80% of your success. The good news is that we can actually study what made Cal AI a $100 million company and break it down into 3 steps that you can follow. So step 1, find your idea. This first step is the one that most people get wrong before they even start building. And it's something that Zach had said before.

It's really just about identifying something that you can derive value from, or you can see someone around you deriving value from. I think that's the best way to come up with an idea and build it out, because if you are your ideal user, you'll know exactly what to build.

That is such an important mindset shift because most people think you start with the product, you build something cool, and then you figure out how to sell it. But Zach did the opposite and he started with the problem and then he built a simple version of the solution. And this is the right way to start building an app. People don't download apps because they look good or because they have extra space on their phone. They download apps because the app solves a very specific problem in their lives. For example, Uber solved the problem of getting a ride without calling a cab and waiting 30 minutes. Duolingo solved the problem of language courses being too expensive and too boring. And Cal AI solved the problem of tedious calorie weighing and tracking. Every successful app starts with one core feature that makes someone say, I need that. So if you're watching this and thinking about building something, here's exactly what I'd do. First, think about your own life. What's a problem that you've run into that frustrates you and how could you solve it? Then look at what's already out there and find outdated solutions. For example, MyFitnessPal had been around for over a decade. It was bloated, complicated, and hadn't innovated in years, and that created the opportunity to make something simpler and faster with AI. You can start to look at the top apps in different categories and try them out to see which ones feel old or which ones are doing something that AI could make 10 times easier for the actual user. And then once you have that idea, build the simplest possible version that you can using AI tools like Cloud Code or Antigravity or Base44. and that way you can move really fast. And moving fast is really important because just how you got that idea, other people can get it too. Cal AI has a ton of copycats, but the reason why Cal AI won is because they got into the market faster and they capitalized on that. So don't spend 6 months perfecting something that nobody has used yet. Get it out there, get real feedback, and iterate. Because just having a great product that solves a real problem, that's only the first piece of the puzzle. Without getting anyone in front of it and getting people to actually use it, nobody will obviously know that your app exists. And that brings me into step 2, which is the thing that made Cal AI grow so fast.

If you had a perfect app, but the worst marketing, you would get no downloads. If you had the worst app, but amazing marketing, you would still get downloads and you'd make some money from those people, even though it's probably like very small conversion rate. So marketing eats just building.

What Zach did to grow in a highly competitive market like fitness was reinvest almost all of the money that they made back into making sure that people knew about the app. So Zach sent hundreds of DMs each day to fitness creators on TikTok and Instagram. At first, almost nobody responded, but he kept going until he found creators willing to work with him and create some ads for the app. But they didn't ask influencers to do any hard selling like, hey guys, this video is sponsored by Calii. Instead, they told the creator to make their regular content, and somewhere in the first 15 seconds, they'll show themselves using Calii. They simply had to add a section where they snap a picture of food and let the calories pop up on the screen. And because the concept of scanning your food and instantly seeing calories is so visual, people watching would immediately notice it and flood into the comments asking, what app is that? And this works so well because if you see a traditional ad that says, "Download Cal AI," your brain immediately just kind of tells you to ignore it. But when you see a fitness creator you've been following for years scanning their lunch, your brain won't even think that it's an ad. It feels more like getting a recommendation from a friend. You don't trust a billboard, but when your friend says, "Yo, try this app," you download it that night. So here's what you can do to get your app in front of people. First, find 20 to 30 creators in whatever market your app is. They don't need to be huge. Even someone with a few thousand followers works. Then DM them. Tell them what your app does and show them why their audience would care about it and offer a flat rate for a bundle of videos. But most importantly, give them complete creative freedom. They know what works with their audience, so just give them the app and tell them to show it in the first 15 seconds of the video. The less that it looks like an ad, the better it will work. Now the fourth step is to track everything. So look at when the video was posted, how many views it got, and what your downloads and revenue looked like on that same day. This is how you figure out which influencers and types of content work best. And from there, it's just a matter of doing more of what's working, signing more creators and getting more users. Okay, step 3 is to build predictable income. So a lot of people think that once someone downloads your app, the deal is done, but it's actually just starting. Cal AI has a lot of copycats trying to do the same thing, so they know that convincing someone to download their app is gonna be hard. Some months they could add thousands of new users, but other months they could only add maybe a couple hundred. So to build predictable revenue, they need to make sure that every single user they already had keeps using Cal AI. If users downloaded the app, used it for a week, and then went with the competition, the whole business model falls apart. So how did Callii do it? Well, it comes down to 3 strategies, and the first one starts before users even start snapping pictures. When you first open the app, it asks you a series of questions. What's your weight? What's your goal weight? Why are you trying to lose or gain weight? How is this going to improve your life? And the reason is that when you ask more personal questions about goals and motivations, it turns into a higher conversion rate. Because by the time someone has answered 10 questions about why they want to get healthier, they've already invested time and emotional energy. So when the subscription page pops up, paying $30 for the year feels like the obvious next step. The second strategy comes back to that core product decision that we talked about earlier. They made the app so simple that using it was basically effortless. You take a picture, you get your calories, and it's done. The whole interaction takes maybe 5 seconds. Compare that to a generic fitness app where you're scrolling through databases, searching for your food, putting it on a scale, and manually adjusting portions. Cal.ai was able to remove that friction, and that's the key insight here. The less effort that it takes to use your app every day, the more likely people are to keep using it. They also added small features that reinforce the habit, like daily streaks, simple dashboard showing your progress and health score that told you how well you were eating. Now, these aren't groundbreaking features, but they give users a reason to come back and check in every single day. And if you're using something every single day, then it's hard to justify using something else. And here's why this matters for the long run. When your monthly revenue is solid and predictable, that's when your app becomes attractive to bigger companies and when the acquisition offers actually start to come in. So Kaliye, selling for millions, proved that the opportunity right now is real. A teenager with no investors or fancy office built an AI app into a company worth hundreds of millions of dollars. And the tools available today are even better than what he had when he started. So you can do what Zach did in less time. But this window is not going to stay open forever. The AI space is moving insanely fast, so you need to act with speed and not waste time. That's why I created a roadmap file based on Call AI's success to help give you clarity on the steps that you need to follow. You can download this for completely free. It's inside of my Free School community where you can get more information about how to use AI tools like Claude Code to build a business from scratch. You can join for free with the link in the description. Anyways, that's gonna do it for today's video. As always, thanks for staying until the end, and I'll see you guys in the next one. Thanks everyone.