Setting up a Progressive Web Application (PWA) primarily involves creating two key files: a Web App Manifest and a Service Worker. These files allow your website to be "installable" on a user's device and work offline.
Here’s a step-by-step guide to convert a basic website into a PWA.
The Core Components
A PWA has two essential building blocks:
Web App Manifest (
manifest.json
): A JSON file that tells the browser about your application—its name, icon, start URL, and theme colors. This is what enables the "Add to Home Screen" or "Install" prompt.Service Worker (
sw.js
): A JavaScript file that runs in the background, separate from your web page. It acts as a proxy between the browser and the network, enabling features like offline access by intercepting requests and serving cached assets.
Prerequisite: Your site must be served over HTTPS. Service workers have the power to intercept and modify network requests, so a secure connection is mandatory for security. (For local development, localhost
is considered a secure origin).
Step 1: Create the Web App Manifest
First, create a file named manifest.json
in the root directory of your project. This file will define how your app appears and behaves when installed.
manifest.json
Direct Distribution:
PWAs can be installed directly from any website through the browser
Users visit your website and get a prompt to "Add to Home Screen" or "Install"
No app store approval process or fees required
App Store Options: However, you can also distribute PWAs through app stores if you want:
Google Play Store: Supports PWAs through Trusted Web Activity (TWA) wrapper
Microsoft Store: Has good PWA support
Apple App Store: More restrictive - requires additional native wrapper and may need extra functionality
Benefits of Direct Distribution:
Instant updates (no app store review delays)
No platform fees (typically 15-30%)
Cross-platform compatibility
Easier A/B testing and feature rollouts
Direct relationship with users
Hybrid Approach: Many companies do both - distribute directly via web while also publishing to app stores for discoverability. This gives you the flexibility of web distribution plus the marketing benefits of app store presence.