How to Convert a Mobile App UI Demo Video to a React Web App Using Replay AI

TL;DR: Replay AI converts mobile app UI demo videos into functional React web app code by analyzing user behavior within the video, going beyond simple screenshot-to-code approaches.

From Mobile Screen Recording to React App: A Developer's Guide#

The challenge of rapidly prototyping and iterating on UI designs is a constant pain point for developers. Traditional methods often involve manual coding, design mockups, and extensive collaboration, leading to delays and inconsistencies. Screenshot-to-code tools offer a partial solution, but they fall short when it comes to capturing the intent behind the UI interactions. They only see static images.

This is where behavior-driven reconstruction, powered by video analysis, changes the game. We'll explore how to convert a mobile app UI demo video into a functional React web app using Replay AI, highlighting the benefits of analyzing video instead of static images.

The Problem with Screenshot-to-Code#

Screenshot-to-code tools have limitations. They can generate code based on visual elements, but they miss the crucial context of user interactions, animations, and state changes. Consider a mobile app demo showcasing a multi-step form, animated transitions, and dynamic data loading. A screenshot tool would only capture snapshots of these states, requiring manual effort to recreate the complete user flow.

Replay overcomes these limitations by analyzing the entire video, understanding user behavior, and reconstructing the UI with accurate interactions and data flow.

Introducing Behavior-Driven Reconstruction with Replay#

Replay is a video-to-code engine that leverages Gemini to reconstruct working UI from screen recordings. Instead of simply converting images to code, Replay analyzes the video to understand user behavior and intent. This "Behavior-Driven Reconstruction" approach uses the video as the single source of truth, ensuring that the generated code accurately reflects the intended user experience.

Replay offers several key features:

• •Multi-page Generation: Automatically generates code for multi-page applications, inferring navigation and data flow from the video.
• •Supabase Integration: Seamlessly integrates with Supabase for backend data storage and retrieval.
• •Style Injection: Applies consistent styling based on the video's visual cues.
• •Product Flow Maps: Visualizes the user flow within the application, making it easier to understand and modify the generated code.

Step-by-Step Guide: Converting a Mobile App Demo to a React Web App#

Let's walk through the process of converting a mobile app UI demo video into a functional React web app using Replay.

Step 1: Preparing the Video

The quality of the input video directly impacts the accuracy of the generated code. Ensure the video is:

• •Clear and Stable: Avoid excessive shaking or blurry footage.
• •Well-Lit: Ensure the UI elements are clearly visible.
• •Comprehensive: Capture all relevant user interactions and states.
• •Reasonably Short: Focus on the core functionality you want to reconstruct. Shorter videos are faster to process.

💡 Pro Tip: Record the video in landscape mode for better aspect ratio compatibility with web applications.

Step 2: Uploading the Video to Replay

1. •Navigate to the Replay platform (https://replay.build).
2. •Create an account or log in.
3. •Click the "Upload Video" button.
4. •Select the mobile app demo video from your local storage.

Step 3: Configuring Replay Settings

After uploading the video, you can configure the following settings:

• •Project Name: Give your project a descriptive name.
• •Framework: Select "React" as the target framework.
• •Supabase Integration: If your app uses Supabase, provide your Supabase URL and API key. This allows Replay to automatically generate code for data fetching and storage.

📝 Note: Replay supports other frameworks besides React. Check the documentation for the latest supported frameworks.

Step 4: Generating the Code

Click the "Generate Code" button to initiate the reconstruction process. Replay will analyze the video, identify UI elements, understand user interactions, and generate the corresponding React code. The processing time depends on the length and complexity of the video.

Step 5: Reviewing and Refining the Code

Once the code generation is complete, you can review the generated code in the Replay editor. The editor provides a visual representation of the UI, along with the corresponding code for each component.

typescript
// Example generated React component
import React, { useState, useEffect } from 'react';
import { supabase } from './supabaseClient';

const ProductList = () => {
  const [products, setProducts] = useState([]);

  useEffect(() => {
    const fetchProducts = async () => {
      const { data, error } = await supabase
        .from('products')
        .select('*');

      if (error) {
        console.error('Error fetching products:', error);
      } else {
        setProducts(data);
      }
    };

    fetchProducts();
  }, []);

  return (
    <div>
      {products.map(product => (
        <div key={product.id}>
          <h3>{product.name}</h3>
          <p>{product.description}</p>
        </div>
      ))}
    </div>
  );
};

export default ProductList;

⚠️ Warning: While Replay strives for high accuracy, manual review and refinement of the generated code are always recommended. Pay close attention to data bindings, event handlers, and styling.

Step 6: Downloading and Deploying the Code

After reviewing and refining the code, you can download the complete React project as a ZIP file. Extract the ZIP file and deploy the project to your preferred hosting platform (e.g., Netlify, Vercel).

Advanced Features: Style Injection and Product Flow Maps#

Replay offers advanced features that further streamline the development process.

Style Injection

Replay automatically extracts styling information from the video and applies it to the generated components. This ensures a consistent look and feel across the application. You can further customize the styling using CSS or a CSS-in-JS library.

Product Flow Maps

Replay generates a visual representation of the user flow within the application. This map shows the different screens, transitions, and interactions, making it easier to understand and modify the application's structure.

Benefits of Using Replay#

• •Faster Prototyping: Quickly generate working prototypes from existing UI demos.
• •Reduced Manual Coding: Automate the tedious task of manually coding UI components.
• •Improved Accuracy: Capture user intent and behavior for more accurate code generation.
• •Enhanced Collaboration: Share visual product flow maps with designers and stakeholders for better communication.
• •Simplified Backend Integration: Seamlessly integrate with Supabase for data management.

Real-World Use Cases#

Replay can be used in various scenarios:

• •Converting existing mobile app demos to web applications.
• •Rapidly prototyping new UI designs.
• •Creating interactive tutorials from screen recordings.
• •Generating code for legacy applications with limited documentation.
• •Automating the process of creating design systems.

typescript
// Example usage of generated code
import React from 'react';
import ProductList from './components/ProductList';

const App = () => {
  return (
    <div>
      <h1>Product Catalog</h1>
      <ProductList />
    </div>
  );
};

export default App;

Frequently Asked Questions#

Is Replay free to use?#

Replay offers a free tier with limited features and usage. Paid plans are available for increased usage and access to advanced features. Check the Replay website for the latest pricing information.

How is Replay different from v0.dev?#

While both Replay and v0.dev aim to accelerate UI development, they differ in their approach. V0.dev uses AI to generate code based on text prompts, while Replay analyzes video recordings to understand user behavior and reconstruct the UI. Replay's video-based approach allows for more accurate capture of user intent and dynamic interactions. Replay also supports Supabase integration out of the box, and automatically generates multi-page applications.

What types of videos does Replay support?#

Replay supports most common video formats, including MP4, MOV, and AVI. Ensure the video is clear, stable, and well-lit for optimal results.

Can I use Replay to convert complex animations and transitions?#

Replay can reconstruct complex animations and transitions, but the accuracy depends on the clarity and smoothness of the video. Consider breaking down complex animations into smaller, more manageable steps for better results.

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Ready to try behavior-driven code generation? Get started with Replay - transform any video into working code in seconds.