# Best practices — Progressive Web Apps

Source: https://www.geekswithgeeks.com/en/pwa/pwa-best-practices

> Follow proven best practices for robust, performant, and user-friendly PWAs.

## PWA excellence checklist

Best practices include: HTTPS always, responsive design, fast load times (under 3s), clear install prompts, proper error handling, accessibility, and comprehensive testing.

## Progressive enhancement patterns

Build with progressive enhancement: core functionality works without JavaScript.

```html
<!-- Fallback for no JS -->
<noscript>This app requires JavaScript. Please enable it.</noscript>

<!-- Base functionality with forms -->
<form method="POST" action="/api/save">
  <input type="text" name="task" required>
  <button type="submit">Save</button>
</form>

<!-- Enhanced with JS/PWA -->
<script>
  document.querySelector('form').addEventListener('submit', async e => {
    e.preventDefault();
    // Use PWA features: offline sync, IndexedDB, etc.
  });
</script>
```

Output:

```
App works without JavaScript and enhanced with PWA features when available.
```

## A common trap

Never assume PWA features are available. Always check with feature detection (if ('serviceWorker' in navigator)) before using them.