独立开发者用UGC矩阵与AB测试打造月入16万美金健身App

I launched Symmetry a year ago, and now it's one of the biggest names in one of the most saturated app markets.

This is Mauro. He's 22, and in just 1 year, he built an app that makes over $160,000 a month. But, this isn't really a story about the app he built. It's more of a story about how he decides what to build.

First, we built what we [music] wanted, terrible idea. Second, we built what users wanted, mediocre. And now we approach a methodical and scientific way of actually building useful things.

Most builders just ship features and hope they work, but Mauro does it differently. He treats every feature like a scientific experiment, and I think it's the number one reason his app is so successful.

Adding one screen, it's increased 3% retention. That is why you have to AB test everything.

So, I asked Mauro to come on to the channel to break down this entire approach. In this episode, we'll dive into the app that he built that makes over $160,000 a month, why most builders are wasting so much time on features that won't move the needle, and his approach on how to build apps the right way in 2026. All right, let's dive in. I'm Pat Walls, and this is Starter Story. All right, Mauro, Gus and I would love to welcome you to the Starter Story channel.

So, tell us about who you are, what app you built, and what's your story.

So, my name is Mauro. I'm 22 years old, and I like to gym so much that I built Symmetry, the fastest growing fitness app in the Spanish market. I launched Symmetry like a year ago, and now it's one of the biggest names in one of the most saturated app markets. And today, I want to share all the tactics of how I did it.

All right, Mauro, uh thanks for being here. Could you just pull up your app, tell us what it is, who your users are, and then pull up your revenue dashboard to show off that this is legit.

Okay, so basically, it's a gym tracking app. So, you can track your workouts and track your weight and reps for different exercises. And currently, we are in the Spanish markets, mainly in Spain and Mexico. Okay, so this is our revenue cut dashboard. You can see we're currently at around 160k monthly revenue. And we currently have around 3 million downloads both across iOS and Android.

But what I think is super cool about what you built is that you built this gym app, but it's sort of localized to the LATAM market, the Spanish market. There's plenty of gym apps in the US, and then finding this sort of niche. This is clearly working. It's doing over $160,000 in revenue in the last 30 days, which is cool. And we're going to talk all about the growth, but before we do, I want to understand a little bit about your background.

Had you always been building apps? What's your background? How did you get to this point?

Growing up, I was actually obese, and the gym is what helped me a lot. The reason I built Symmetry was to share this improvement I had in my life with others. Before building Symmetry, I was actually a fitness YouTuber, and so were my co-founders. And we were like, "Okay, YouTube is good, but we want to help more people. How can we do this?" And that is when we joined together to build Symmetry.

All right, before we get into some of the stuff we want to talk about when it comes to like building the product, let's talk about growth. So, maybe just give us a little bit of a sense of your growth timeline. You said you launched like a year ago. Talk to us about your growth timeline in the last year.

So, we launched on 6th of June of last year, so just barely over a year. When we first launched, we had a very small spike in downloads due to our previous YouTuber era, but then we had to transform into another acquisition channel that was reliable and scalable. And over summer, we were trying to do UGC. We barely were at around 30k downloads. At the end of quarter four, we did see a slight increase, but it was in January, in Q1, when we saw a spike.

Maybe people go to the gym more in January. And since then, we've stabilized.

Awesome. And then let's talk about some of the tactics that you used to grow. I think you just mentioned UGC. What were some of the main growth strategies you used to grow this app to over $150,000 a month?

So, first when we launched, we had this YouTube community. And we thought it was going to be really good for growing the app. It wasn't. So, we started to try new things. We went into influencer marketing. Well, it didn't work. So, we tried other methods and that is when we found GC. We were really good at it and we just did more and better. Okay, so this is our internal dashboard. In the last year, we have posted nearly 80,000 videos.

We have more than 500 accounts and we have done nearly 8 billion views in the last year. Something that really works for us is we segment the videos into formats. This was a format that works really good for us where you see the lock screen of your iPhone with a notification. In this case, your girlfriend like leaving you and below a symmetry notification saying, "Go to the gym and workout." Well, it works so well that we track all of the videos and we even have sub formats to segment them even more.

And this video went extremely viral. You can see 17 million views. So, the way we pay our creators and how much are we spending on marketing? Basically, we give nearly half of the revenue to the creators. So, we pay them a lot. This way they are incentivized to do more content and to stay in symmetry for the long run.

Okay, thanks for sharing all that about how you grew. I think it's super cool. We've done a ton of videos on UGC. I don't think that's anything new and you can go and check out a bunch of the content that they create and and see some of the examples. But I actually thought was super cool and we had chatted before, Mauro, is you told me you have like sort of like a different approach to building. And when we started digging into it, I thought it was super cool because you got this app to $160,000 a month within 1 year and that's like really, really fast.

Like usually you'll see, you know, maybe get to 30 or 50K within a year. You did it super fast and I think one of those reasons was sort of you have this sort of different approach to building that you shared with me where things just kind of started working right away. So, could you share with me that approach to like how you knew what to build, what features to build?

Yeah, so we went through three different phases when building Symmetry. First, we built what we wanted. Terrible idea. Second, we built what users wanted like directly from feedback quest. Mediocre. And now we approach a methodical and scientific way of actually building useful things.

Okay, yeah, so I agree. I mean, I see a lot of people that go and just start building stuff. Maybe they ask their AI tool about what to build, or maybe they build based on instincts. But yeah, yours is a little different. Could you dive a little bit more into what you mean by that?

Yeah, so people normally are incorrect about what is important to build and what is not important. [music] Let's say you build a dark theme or a light theme. This may affect like 2% of your daily active users. Whereas, if you AB test the paywall, it's going to affect a lot of users in a radical way. That's why there are like even softwares just to AB test on screen. And apart from the paywall, there are very other important places of your app, and your job is to find those places and AB test them and really exploit all of the metrics from them.

For example, in symmetry our exercise search screen, so the screen you search exercises has a huge impact on activation and retention. Whereas, the screen you log into the app first to see your workouts, we've done a lot of things there and doesn't seem to change anything.

Hey, it's Gus, producer here at Starter Story. I love everything that Maro is breaking down about his process of building