Ai Coding Tools

How to Build a Simple Web App with AI in 3 Hours

By BTW Team4 min read

How to Build a Simple Web App with AI in 3 Hours

Building a web app can feel daunting, especially if you're just starting out. The good news? With the right AI coding tools, you can whip up a simple web app in about three hours. Trust me, I’ve been there, and I know the struggle of juggling multiple tools and trying to figure out what actually works. This guide will help you cut through the noise and get something functional up and running quickly.

Prerequisites: What You Need to Get Started

Before diving in, make sure you have the following:

  • A computer with internet access.
  • Basic understanding of HTML, CSS, and JavaScript. You don’t need to be an expert, but familiarity helps.
  • Accounts on the following tools:
    • GitHub (for version control)
    • A code editor like Visual Studio Code (free)
    • A cloud service like Vercel (free tier available)

Step 1: Choosing Your AI Tool

To integrate AI into your web app, you’ll need a coding tool that simplifies the process. Below is a list of AI coding tools, along with what they do, their pricing, and our honest take on each.

| Tool Name | Pricing | Best For | Limitations | Our Take | |-------------------|-----------------------------|-------------------------------------------|-----------------------------------------|--------------------------------------------| | OpenAI Codex | Free tier + $20/mo | Generating code snippets | Limited to specific languages | We use this for quick code generation. | | Replit | Free tier + $7/mo for pro | Collaborative coding | Performance can lag with heavy apps | Great for quick prototypes. | | GitHub Copilot | $10/mo | Code completion and suggestions | Not perfect, can generate incorrect code| We use this for enhancing our coding speed.| | AI Dungeon | Free tier + $9.99/mo | Story-driven apps | Limited to narrative AI | Not ideal for traditional web apps. | | Bubble | Free tier + $29/mo | Building no-code apps | Less control over customization | We’ve tried it but prefer coding. | | Pipedream | Free tier + $19/mo | Building integrations | Learning curve for beginners | Good for connecting APIs easily. | | DeepAI | Free tier + $5/mo | Image generation | Limited features compared to others | We use it for simple image tasks. | | Streamlit | Free tier + $25/mo | Quick data apps | Requires Python knowledge | Great for data visualization projects. | | AppGyver | Free tier | Rapid app development | Limited to simpler apps | Not used frequently in our stack. | | TensorFlow.js | Free | Implementing AI in web apps | Steep learning curve | Good for those who want to dive deep into AI.| | Glitch | Free tier | Collaborative coding and hosting | Limited resources for larger projects | We love it for community-driven projects. | | Vercel | Free tier | Hosting static sites | Paid tier for advanced features | Our go-to for easy deployments. |

What We Actually Use

In our experience, we typically lean on OpenAI Codex for code generation and Vercel for hosting. This combination allows us to get things up and running quickly without incurring heavy costs.

Step 2: Setting Up Your Development Environment

  1. Create a new repository on GitHub.
  2. Clone it to your local machine.
  3. Open your code editor (like Visual Studio Code) and create the following files:
    • index.html - The main HTML file.
    • style.css - For styling your app.
    • app.js - Where the JavaScript magic happens.

Example Output

Your index.html might look something like this:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <link rel="stylesheet" href="style.css">
    <title>Simple AI App</title>
</head>
<body>
    <h1>Welcome to My AI Web App</h1>
    <script src="app.js"></script>
</body>
</html>

Step 3: Adding AI Functionality

Now, let’s integrate AI. Using OpenAI Codex, you can generate code snippets that add features to your app.

  1. Write a function in app.js to fetch AI responses.
  2. Use the generated code to handle inputs and outputs.

Example Output

Here’s a simple function to call the AI API:

async function fetchAIResponse(input) {
    const response = await fetch('YOUR_AI_API_ENDPOINT', {
        method: 'POST',
        headers: {
            'Content-Type': 'application/json',
        },
        body: JSON.stringify({ prompt: input }),
    });
    const data = await response.json();
    return data.result;
}

Troubleshooting: What Could Go Wrong

  • API Key Issues: Ensure your AI API key is correctly set up. Check for typos or expired keys.
  • CORS Errors: If your browser blocks requests, you may need to configure your server or use a proxy.

What’s Next: Deploying Your Web App

Once your app is functional, you’ll want to deploy it. Using Vercel, follow these steps:

  1. Push your code to GitHub.
  2. Connect your Vercel account to GitHub.
  3. Deploy your app with a single click.

Expect your app to be live within minutes!

Conclusion: Start Here

If you’re a beginner looking to build a simple web app with AI, start with OpenAI Codex and Vercel. They offer the best balance of ease-of-use and functionality without breaking the bank. You can have a functional app ready in just three hours.

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