How I Build Full Stack Apps With AI (Claude Opus 4.6, Antigravity, Manus AI)

Kristoffer · February 20, 2026 · 9 min read

<a href="https://manus.im/redeem?c=B1A16M29" target="_blank" rel="noopener noreferrer" style={{textDecoration: 'underline'}}> {bold ? {children || 'Manus'} : (children || 'Manus')} );

This website made between $25 to $50 million dollars before getting acquired by Salesforce for a reported $419 million. The product? Spiff - a software that combines both Excel and traditional sales software to create a niche product in high demand.

But here's the interesting part. You can now use AI tools to create a near-perfect replica of this exact app in minutes - without knowing anything about coding, advanced design, or user experience principles.

In this post, I'll show you exactly how to use an AI tool called Manus to create a niche-down version of Spiff. You'll go from nothing to having a fully featured app with the potential of making a lot of money.

Why Mobile Apps?

It's a widely known fact that developing mobile apps, specifically for iOS, is one of the easier ways to make money. Here's what most people don't realize: Apple devices tend to attract people with more money to spend. This means by targeting Apple users, you increase the chances of profitability for your app by a lot.

You can of course also build Android and web apps by following this tutorial. When building mobile apps, we use React Native, which means you can publish to both iOS and Android from the same codebase.

The Traditional Problem

Now you might be thinking: "I don't know anything about coding," or "I don't have a lot of free time," or "I don't have a big budget to build an app." Traditionally, you had two options:

  1. Learn mobile app development yourself. This is not very easy. It takes months or even years to master, and sometimes even longer to make decent income from it.
  2. Hire a stacked team of developers. A simple internet search for freelance iOS developers will show you that this is very expensive. Plus, you need very good management skills to work effectively with a highly paid developer team that obviously knows more than you.

But then there's a third option that is basically an unfair advantage: an AI app builder called Manus. With Manus, a complete beginner can build a mobile app that rivals the work of a talented, highly experienced development team. And the best part? You only need to instruct it as you would a person - no coding or design knowledge required.

I've boiled down the entire process into just four simple steps.

Step 1: Building the App

Here's what you need to know about Manus before we begin: it's optimized to understand natural language, which means you need to be as detailed as possible in your interactions with it.

First, head over to braindumper.ai. All you need to do is input your app idea - just brain dump everything you can think of. In this case, we want an app that manages sales commissions and automatically generates statements in real time.

The process is simple:

  1. Enter your app idea into Braindumper
  2. Choose Manus as the platform to optimize the prompt for
  3. Hit the generate button and wait around 10 seconds

The AI generates a prompt with all of the details specialized for app builders like Manus to build a production-ready prototype. You'll get a crafted prompt that includes features you hadn't even thought about yourself.

[!TIP] In the bottom left corner of Braindumper, there's a share button. Share Braindumper with your friends to earn 10 free credits for every friend you refer, and your friends get 10 free credits too.

Now comes the critical part. Open Manus, paste in the generated prompt, and click the button. Manus starts doing all of the complex coding and AI work while you wait. It's essentially building out the entire app from just one prompt.

From my experience in software development, a version like this usually takes a developer many days to build and test. But Manus just did this in a few minutes. Looking through the code shows that the builder is using updated coding standards and patterns that take human developers a long time to master.

Step 2: Iterating the App

After the first build, I noticed something was wrong. The main page pointed directly to the dashboard, but it should be a landing page that shows off all of the app's features to explain how users will benefit from choosing us over the competition. There should be a separate page for users to log in and view the dashboard.

We also needed to change the color scheme to make the app look more lively. All you do is enter the feedback into the Manus chatbot and wait.

Here's where you'll see something really cool: Manus shows its actual thought process. Not only do you see how the AI breaks down complex problems, but it lays everything out in a way that anyone can understand. This means:

Manus created an entire theme in minutes from just a single suggestion. This would have taken a developer at least a day to design and implement.

Third-Party Integrations

Since we're building a commission tracker app, we need to integrate it with third-party CRMs like Salesforce. Watch this - Manus takes this simple request and not only integrates Salesforce, but also other third-party apps I didn't even mention.

Don't be mistaken into thinking that this AI builder is only used by solopreneurs and hobbyists. People are actually using Manus to create MVPs for startups that end up getting serious venture capital funding.

Design Improvements with Images

Manus has a powerful feature to make updates using images. If you want your design page to look like a specific mock-up, just tell Manus to follow the design in the attached image. There's no need to use complex design software or know the details about what makes a certain UI more effective.

Adding Payments

Now for the most important part - building a payment system so you can actually make money. Building payment systems is really complicated, but Manus simplifies the process through its integrations feature.

All you do is ask the AI chat to integrate a subscription plan with the packages you want. You can give it instructions like which features to make premium, how to design the pricing page, and so on. A simple Stripe integration and you're set.

Now we have a Spiff clone that can be marketed to small business owners who want to handle all of their commission data on their smartphones.

If your app has a blog feature or you'd like the landing page optimized for SEO, you can simply ask Manus to integrate SEO features as well.

Step 3: Testing and Security Audits

At this point, all of the hard work is done. But here's the one critical part that most people skip.

Mobile app users usually uninstall an app the first time it stops doing what it's supposed to do. To avoid massive churn, you need to make sure the app works and nothing breaks. This means:

Before high-quality AI app builders came to the market, performance audits were done by teams of professionals and beta testers. It was an expensive and time-consuming process that wasn't even effective most of the time. Now with Manus, you can instruct it to do a performance check and fix any issues it finds.

Security Audit with Claude Opus 4.6

This is where we go from amateur to professional. Download the project and load it into Antigravity to run a proper security audit using Claude's most recent model, Opus 4.6, to uncover any security holes that can expose sensitive user information.

[!TIP] Never skip security audits for sensitive apps. Since your users are trusting you with their business and personal financial data, this step is non-negotiable.

After the security audit, head back to Manus and finish all of the other pre-publication checks:

Always go through the app yourself and make sure it actually works before you launch it.

Step 4: Deploying the App

Now here's where everything comes together. Manus allows you to move from app creation to testing on your device within minutes.

Publishing to the iOS App Store is as simple as clicking the publish button and choosing the platform. You can also create an Android app just as easily by selecting it from the dialog.

One thing to note: the backend service for your app needs to be published separately and must be live before the app is usable. It sounds complicated, but getting this backend working is just as simple as clicking a button.

You will need an Apple Developer Account which costs $99/year. After a few seconds, a build page will appear to guide you on how to create and publish the app to the App Store. Then just wait for it to go through the review process, which can take anywhere from a few minutes to a few days. Usually for me, this takes less than 24 hours.

Final Thoughts

You've just learned how to use Manus to create and publish an app that would have taken developers weeks of effort - all in four simple steps:

  1. Build the initial app with a single prompt via Braindumper and Manus
  2. Iterate on design, features, integrations, and payments
  3. Test performance and run security audits with Claude Opus 4.6
  4. Deploy to the App Store with just a few clicks

Ready to start building?

Happy building!