---

name: mobile description: "Mobile-first patterns - forms, thumb zones, responsive"

Luke Wroblewski - Mobile-First Patterns

Design for mobile constraints first. Desktop is mobile with more space.

Core Philosophy

Mobile First

Start with the smallest screen, then add. Don't start big and remove.

Why:

• Forces prioritization (no room for clutter)
• Mobile is the hard problem (desktop is easy)
• Touch constraints are stricter
• Performance matters more

Forms are Conversations

Forms are not data entry. They're conversations with users.

Mobile Form Patterns

Input Types

<!-- Use semantic input types for mobile keyboards -->
<input type="email">     <!-- @ symbol visible -->
<input type="tel">       <!-- Number pad -->
<input type="number">    <!-- Numeric keyboard -->
<input type="url">       <!-- .com button -->
<input type="search">    <!-- Search button -->
<input type="date">      <!-- Date picker -->

Top-Aligned Labels

<!-- Labels above inputs (not beside) -->
<div class="field">
  <label for="email">Email address</label>
  <input type="email" id="email">
</div>

.field label {
  display: block;
  margin-bottom: 4px;
  font-size: 14px;
  font-weight: 500;
}

.field input {
  width: 100%;
  min-height: 44px;
}

Inline Validation

// Validate on blur, not on change
input.addEventListener('blur', validateField);

// Show success, not just errors
function showValidation(field, isValid) {
  field.classList.remove('error', 'success');
  field.classList.add(isValid ? 'success' : 'error');
}

Smart Defaults

<!-- Pre-fill when possible -->
<input type="tel" autocomplete="tel">
<input type="email" autocomplete="email">
<select>
  <option selected>United States</option> <!-- Most common -->
</select>

<!-- Reduce typing -->
<input type="date" value="2024-01-15"> <!-- Today's date -->

Prescriptive Form Rules

Field Order

1. Required fields first
2. Related fields grouped
3. Optional fields last (or behind "Show more")
4. Never ask for info you can infer

Reducing Input

DON'T                           DO
─────────────────────────────────────────
Name: [First] [Last]     →     Name: [Full name]
Address line 2           →     (Remove - rarely used)
Country dropdown         →     (Auto-detect from IP)
Confirm email            →     (Just show what they typed)
Phone format             →     (Accept any format, parse)

Error Messages

<!-- Bad -->
<span class="error">Invalid input</span>

<!-- Good -->
<span class="error">
  <svg><!-- Error icon --></svg>
  Enter a valid email like name@example.com
</span>

Rules:

• Specific, not generic
• Show what valid looks like
• Place below the field
• Don't clear the input (let them fix it)

Mobile Navigation

Bottom Navigation (Primary)

<nav class="bottom-nav">
  <a href="/" class="nav-item active">
    <svg><!-- Home icon --></svg>
    <span>Home</span>
  </a>
  <a href="/search" class="nav-item">
    <svg><!-- Search icon --></svg>
    <span>Search</span>
  </a>
  <a href="/profile" class="nav-item">
    <svg><!-- Profile icon --></svg>
    <span>Profile</span>
  </a>
</nav>

.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  display: flex;
  background: white;
  border-top: 1px solid var(--gray-200);
  padding-bottom: env(safe-area-inset-bottom); /* iPhone notch */
}

.nav-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 8px;
  min-height: 56px;
}

Rules:

• Maximum 5 items
• Icons + labels (not just icons)
• Active state visible
• Safe area for notch devices

Hamburger Alternative

Instead of hidden menus, use:

• Bottom navigation (most common actions)
• Tab bar (content categories)
• Priority+ pattern (show what fits, ... for rest)

<!-- Priority+ navigation -->
<nav class="priority-nav">
  <a href="/home">Home</a>
  <a href="/products">Products</a>
  <a href="/about">About</a>
  <button class="more">More...</button>
</nav>

Responsive Breakpoints

/* Mobile first: base styles are mobile */
.container {
  padding: 16px;
}

/* Tablet */
@media (min-width: 640px) {
  .container {
    padding: 24px;
  }
}

/* Desktop */
@media (min-width: 1024px) {
  .container {
    padding: 32px;
    max-width: 1200px;
    margin: 0 auto;
  }
}

Content Adaptation

Mobile	Tablet	Desktop
Stack (1 col)	2 columns	3-4 columns
Bottom nav	Bottom nav or sidebar	Sidebar
Full-width cards	Card grid	Card grid with filters
Single action	Multiple actions visible	All actions visible

Touch Targets

/* Minimum sizes */
.touch-target {
  min-width: 44px;
  min-height: 44px;
}

/* Spacing between targets */
.button + .button {
  margin-left: 8px;
}

/* Padding over size for links */
a.touch-target {
  padding: 12px;
  margin: -12px;  /* Expand hit area without visual change */
}

Performance Rules

1. Critical CSS inline
2. Images lazy-loaded
3. Font loading: swap (show text immediately)
4. No blocking resources
5. First meaningful paint < 1.5s on 3G

<!-- Lazy loading -->
<img src="placeholder.jpg" data-src="real-image.jpg" loading="lazy">

<!-- Font display -->
<link rel="preload" href="font.woff2" as="font" crossorigin>

Review Checklist

• Semantic input types for all fields
• Labels above inputs (not beside)
• Touch targets 44px minimum
• Bottom navigation for primary actions
• Inline validation on blur
• Error messages are specific
• Safe area respected (notch devices)
• Works on 3G connection

Anti-Patterns

Bad	Why	Fix
Labels beside inputs	Hard on narrow screens	Labels above
Hamburger for primary nav	Hidden = unused	Bottom nav
Placeholder as label	Disappears on input	Real label
Dropdown for < 5 options	Requires two taps	Radio buttons
Confirm password field	Annoying, little value	Show/hide toggle
Country dropdown first	Rare use case	Auto-detect, last

Wroblewski Score

Score	Meaning
10	Mobile-native, forms are effortless
7-9	Works on mobile but desktop-first thinking
4-6	Pinch/zoom required, forms painful
0-3	Unusable on mobile

Integration

Combine with:

• /interaction - Input fundamentals these patterns build on
• /usability - Psychology of form completion
• /components - Components that implement these patterns