App Design for PWAs

UI/UX Design Principles

PWAs should feel like natural apps. Design principles include:

• Mobile-first: Design for small screens first, then enhance for larger screens.
• Fast feedback: Respond to user actions within 100ms.
• Smooth transitions: Use CSS animations and transitions for fluid navigation.
• Offline-aware: Gracefully handle offline states with informative UI.

Responsive Layouts

Use CSS Grid, Flexbox, and media queries to create adaptive layouts that work on all screen sizes.

/* Responsive app layout */
.app-layout {
  display: grid;
  grid-template-areas:
    "header"
    "main"
    "footer";
  grid-template-rows: 56px 1fr auto;
  min-height: 100vh;
}

@media (min-width: 768px) {
  .app-layout {
    grid-template-columns: 240px 1fr;
    grid-template-areas:
      "header header"
      "sidebar main"
      "sidebar footer";
  }
}

/* Touch-friendly targets */
button, a, input {
  min-height: 48px;
  min-width: 48px;
}

/* Pull-to-refresh simulation */
.pull-to-refresh {
  touch-action: pan-y;
  overscroll-behavior: contain;
}

Accessibility (A11y)

PWAs must be accessible to all users:

• Use semantic HTML elements (<nav>, <main>, <article>)
• Provide ARIA labels for interactive elements
• Ensure color contrast ratios (WCAG AA: 4.5:1)
• Support keyboard navigation
• Test with screen readers (VoiceOver, NVDA)

<!-- Accessible navigation -->
<nav aria-label="Main navigation" role="navigation">
  <button aria-label="Open menu">
    <span class="hamburger" aria-hidden="true"></span>
  </button>
  <ul role="menubar">
    <li role="none">
      <a role="menuitem" href="/" aria-current="page">Home</a>
    </li>
  </ul>
</nav>

App-like Look & Feel

• Use system fonts (-apple-system, Segoe UI) for native feel
• Add safe-area-inset for notched devices
• Use CSS env(safe-area-inset-*) for proper padding
• Implement swipe gestures (with libraries like Swiper or Hammer.js)

/* Safe area support for notched devices */
body {
  padding-top: env(safe-area-inset-top);
  padding-bottom: env(safe-area-inset-bottom);
  padding-left: env(safe-area-inset-left);
  padding-right: env(safe-area-inset-right);
}

/* System font stack */
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI',
    Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}