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Apple HIG Designer

Design beautiful, native iOS apps following Apple's Human Interface Guidelines (HIG). Create accessible, intuitive interfaces with native components, proper typography, semantic colors, and Apple's design principles.

What This Skill Does

Helps you design and build iOS apps that feel native and follow Apple's guidelines:

• Generate iOS Components - Create SwiftUI and UIKit components
• Validate Designs - Check compliance with Apple HIG
• Ensure Accessibility - VoiceOver, Dynamic Type, color contrast
• Apply Design Principles - Clarity, Deference, Depth
• Use Semantic Colors - Automatic dark mode support
• Implement Typography - San Francisco font system
• Follow Spacing - 8pt grid system and safe areas

Apple's Design Principles

1. Clarity

Make content clear and focused.

Text is legible at every size, icons are precise and lucid, adornments are subtle and appropriate, and a focus on functionality drives the design.

// ✅ Clear, focused content
Text("Welcome back, Sarah")
    .font(.title)
    .foregroundColor(.primary)

// ❌ Unclear, cluttered
Text("Welcome back, Sarah!!!")
    .font(.title)
    .foregroundColor(.red)
    .background(.yellow)
    .overlay(Image(systemName: "star.fill"))

2. Deference

UI helps people understand and interact with content, but never competes with it.

The interface defers to content, using a light visual treatment that keeps focus on the content and gives the content room to breathe.

// ✅ Content-focused
VStack(alignment: .leading, spacing: 8) {
    Text("Article Title")
        .font(.headline)
    Text("Article content goes here...")
        .font(.body)
        .foregroundColor(.secondary)
}
.padding()

// ❌ Distracting UI
VStack(spacing: 8) {
    Text("Article Title")
        .font(.headline)
        .foregroundColor(.white)
        .background(.blue)
        .border(.red, width: 3)
}

3. Depth

Visual layers and realistic motion convey hierarchy and help people understand relationships.

Distinct visual layers and realistic motion impart vitality and facilitate understanding. Touch and discoverability heighten delight and enable access to functionality without losing context.

// ✅ Clear depth hierarchy
ZStack {
    Color(.systemBackground)

    VStack {
        // Card with elevation
        CardView()
            .shadow(radius: 8)
    }
}

// Using blur for depth
Text("Content")
    .background(.ultraThinMaterial)

iOS UI Components

Navigation Patterns

1. Navigation Bar

Top bar for navigation and actions.

NavigationStack {
    List {
        Text("Item 1")
        Text("Item 2")
    }
    .navigationTitle("Title")
    .navigationBarTitleDisplayMode(.large)
    .toolbar {
        ToolbarItem(placement: .navigationBarTrailing) {
            Button("Add") {
                // Action
            }
        }
    }
}

Guidelines:

• Use large titles for top-level views
• Use inline titles for detail views
• Keep actions relevant to current context
• Maximum 2-3 toolbar items

2. Tab Bar

Bottom navigation for top-level destinations.

TabView {
    HomeView()
        .tabItem {
            Label("Home", systemImage: "house")
        }

    SearchView()
        .tabItem {
            Label("Search", systemImage: "magnifyingglass")
        }

    ProfileView()
        .tabItem {
            Label("Profile", systemImage: "person")
        }
}

Guidelines:

• 3-5 tabs maximum
• Use SF Symbols for icons
• Labels should be concise (one word)
• Never hide or disable tabs
• Don't use tab bar with toolbar in same view

3. List

Scrollable list of items.

List {
    Section("Today") {
        ForEach(items) { item in
            NavigationLink {
                DetailView(item: item)
            } label: {
                HStack {
                    Image(systemName: item.icon)
                        .foregroundColor(.accentColor)
                    Text(item.title)
                }
            }
        }
    }
}
.listStyle(.insetGrouped)

List Styles:

• .plain - Edge-to-edge rows
• .insetGrouped - Rounded, inset sections (iOS default)
• .sidebar - For navigation sidebars

4. Sheet (Modal)

Present content modally.

struct ContentView: View {
    @State private var showSheet = false

    var body: some View {
        Button("Show Details") {
            showSheet = true
        }
        .sheet(isPresented: $showSheet) {
            DetailView()
                .presentationDetents([.medium, .large])
        }
    }
}

Sheet Detents:

• .medium - Half screen
• .large - Full screen
• Custom heights available

Form Controls

1. Button

Primary action control.

// Filled button (primary action)
Button("Continue") {
    // Action
}
.buttonStyle(.borderedProminent)

// Bordered button (secondary action)
Button("Cancel") {
    // Action
}
.buttonStyle(.bordered)

// Plain button (tertiary action)
Button("Learn More") {
    // Action
}
.buttonStyle(.plain)

Button Hierarchy:

1. Prominent - Primary action (one per screen)
2. Bordered - Secondary actions
3. Plain - Tertiary actions, links

Guidelines:

• Minimum tap target: 44x44 points
• Use verbs for button labels
• Make destructive actions require confirmation

2. TextField

Text input control.

@State private var username = ""
@State private var password = ""

VStack(alignment: .leading, spacing: 16) {
    // Standard text field
    TextField("Username", text: $username)
        .textFieldStyle(.roundedBorder)
        .textContentType(.username)
        .textInputAutocapitalization(.never)
        .autocorrectionDisabled()

    // Secure field
    SecureField("Password", text: $password)
        .textFieldStyle(.roundedBorder)
        .textContentType(.password)
}

Text Content Types:

• .username - Username field
• .password - Password field
• .emailAddress - Email field
• .telephoneNumber - Phone number
• .creditCardNumber - Credit card

3. Toggle

Boolean control (switch).

@State private var isEnabled = false

Toggle("Enable notifications", isOn: $isEnabled)
    .toggleStyle(.switch)

Guidelines:

• Label describes what the toggle controls
• Effect should be immediate
• Use for binary choices only

4. Picker

Selection control.

@State private var selectedSize = "Medium"
let sizes = ["Small", "Medium", "Large"]

// Menu style
Picker("Size", selection: $selectedSize) {
    ForEach(sizes, id: \.self) { size in
        Text(size).tag(size)
    }
}
.pickerStyle(.menu)

// Segmented style (for 2-5 options)
Picker("Size", selection: $selectedSize) {
    ForEach(sizes, id: \.self) { size in
        Text(size).tag(size)
    }
}
.pickerStyle(.segmented)

Picker Styles:

• .menu - Dropdown menu (default)
• .segmented - Segmented control (2-5 options)
• .wheel - Scrollable wheel
• .inline - Inline list (in forms)

Cards and Containers

Card View

struct CardView: View {
    var body: some View {
        VStack(alignment: .leading, spacing: 12) {
            Text("Title")
                .font(.headline)

            Text("Description goes here with some details about the content.")
                .font(.subheadline)
                .foregroundColor(.secondary)
                .lineLimit(2)

            Spacer()

            Button("Action") {
                // Action
            }
            .buttonStyle(.borderedProminent)
        }
        .padding()
        .frame(width: 300, height: 200)
        .background(Color(.systemBackground))
        .cornerRadius(12)
        .shadow(color: .black.opacity(0.1), radius: 8, x: 0, y: 4)
    }
}

Typography

San Francisco Font System

Apple's system font designed for optimal legibility.

// Dynamic Type text styles
Text("Large Title").font(.largeTitle)      // 34pt
Text("Title").font(.title)                 // 28pt
Text("Title 2").font(.title2)              // 22pt
Text("Title 3").font(.title3)              // 20pt
Text("Headline").font(.headline)           // 17pt semibold
Text("Body").font(.body)                   // 17pt regular
Text("Callout").font(.callout)             // 16pt
Text("Subheadline").font(.subheadline)     // 15pt
Text("Footnote").font(.footnote)           // 13pt
Text("Caption").font(.caption)             // 12pt
Text("Caption 2").font(.caption2)          // 11pt

Custom Fonts with Dynamic Type

// Custom font that scales with Dynamic Type
Text("Custom Text")
    .font(.custom("YourFont-Regular", size: 17, relativeTo: .body))

Font Weights

Text("Light").fontWeight(.light)
Text("Regular").fontWeight(.regular)
Text("Medium").fontWeight(.medium)
Text("Semibold").fontWeight(.semibold)
Text("Bold").fontWeight(.bold)
Text("Heavy").fontWeight(.heavy)

Typography Guidelines

Do:

• ✅ Use system font (San Francisco) for consistency
• ✅ Support Dynamic Type for accessibility
• ✅ Use semantic text styles (.headline, .body, etc.)
• ✅ Minimum body text: 17pt
• ✅ Line spacing: 120-145% of font size

Don't:

• ❌ Use too many font sizes (stick to system styles)
• ❌ Make text smaller than 11pt
• ❌ Use all caps for long text
• ❌ Disable Dynamic Type

Colors

Semantic Colors

Colors that automatically adapt to light/dark mode.

// UI Element Colors
Color(.label)                    // Primary text
Color(.secondaryLabel)           // Secondary text
Color(.tertiaryLabel)            // Tertiary text
Color(.quaternaryLabel)          // Watermark text

Color(.systemBackground)         // Primary background
Color(.secondarySystemBackground) // Secondary background
Color(.tertiarySystemBackground)  // Tertiary background

Color(.systemFill)               // Fill colors
Color(.secondarySystemFill)
Color(.tertiarySystemFill)
Color(.quaternarySystemFill)

Color(.separator)                // Separator lines
Color(.opaqueSeparator)          // Non-transparent separator

System Colors

// Standard system colors (adapt to dark mode)
Color(.systemRed)
Color(.systemOrange)
Color(.systemYellow)
Color(.systemGreen)
Color(.systemMint)
Color(.systemTeal)
Color(.systemCyan)
Color(.systemBlue)
Color(.systemIndigo)
Color(.systemPurple)
Color(.systemPink)
Color(.systemBrown)
Color(.systemGray)

Custom Colors with Dark Mode

// Define adaptive color
extension Color {
    static let customBackground = Color("CustomBackground")
}

// In Assets.xcassets, create color set with:
// - Any Appearance: #FFFFFF
// - Dark Appearance: #000000

Color Contrast Guidelines

WCAG AA Compliance:

• Normal text: 4.5:1 contrast ratio minimum
• Large text (24pt+): 3:1 contrast ratio minimum
• UI components: 3:1 contrast ratio

Custom colors:

• Test with Increase Contrast enabled
• Aim for 7:1 for critical text
• Provide sufficient contrast in both modes

Spacing and Layout

8-Point Grid System

All spacing should be multiples of 8.

// Spacing values
.padding(8)      // 8pt
.padding(16)     // 16pt (standard)
.padding(24)     // 24pt
.padding(32)     // 32pt
.padding(40)     // 40pt
.padding(48)     // 48pt

// Edge-specific padding
.padding(.horizontal, 16)
.padding(.vertical, 24)
.padding(.top, 16)
.padding(.bottom, 16)

Safe Areas

Respect device safe areas.

// Content within safe area (default)
VStack {
    Text("Content")
}

// Extend beyond safe area
VStack {
    Color.blue
}
.ignoresSafeArea()

// Extend top only
VStack {
    Color.blue
}
.ignoresSafeArea(edges: .top)

Touch Targets

Minimum interactive size: 44x44 points.

Button("Tap") {
    // Action
}
.frame(minWidth: 44, minHeight: 44)

Spacing Guidelines

// Component spacing
VStack(spacing: 8) {       // Tight spacing
    Text("Line 1")
    Text("Line 2")
}

VStack(spacing: 16) {      // Standard spacing
    Text("Section 1")
    Text("Section 2")
}

VStack(spacing: 24) {      // Loose spacing
    SectionView()
    SectionView()
}

Accessibility

VoiceOver Support

Screen reader for blind and low-vision users.

// Accessible label
Image(systemName: "heart.fill")
    .accessibilityLabel("Favorite")

// Accessible value
Slider(value: $volume)
    .accessibilityLabel("Volume")
    .accessibilityValue("\(Int(volume * 100))%")

// Accessible hint
Button("Share") {
    share()
}
.accessibilityHint("Shares this item with others")

// Group elements
HStack {
    Image(systemName: "person")
    Text("John Doe")
}
.accessibilityElement(children: .combine)

// Hidden from VoiceOver
Image("decorative")
    .accessibilityHidden(true)

Dynamic Type

Support user's preferred text size.

// Automatically supported with system fonts
Text("This text scales")
    .font(.body)

// Limit scaling (if necessary)
Text("This text has limits")
    .font(.body)
    .dynamicTypeSize(...DynamicTypeSize.xxxLarge)

// Custom font with Dynamic Type
Text("Custom font")
    .font(.custom("YourFont", size: 17, relativeTo: .body))

Color Blindness

Design for color-blind users.

// Don't rely on color alone
HStack {
    Image(systemName: "checkmark.circle.fill")
        .foregroundColor(.green)
    Text("Success")
}

// Not just color
Circle()
    .fill(.green)
// ❌ Color only

// Better with shape/icon
HStack {
    Image(systemName: "checkmark.circle.fill")
    Circle().fill(.green)
}
// ✅ Color + shape

Reduce Motion

Respect user's motion preferences.

@Environment(\.accessibilityReduceMotion) var reduceMotion

var animation: Animation {
    reduceMotion ? .none : .spring()
}

Button("Animate") {
    withAnimation(animation) {
        // Animate
    }
}

Increase Contrast

Support high contrast mode.

@Environment(\.colorSchemeContrast) var contrast

var textColor: Color {
    contrast == .increased ? .primary : .secondary
}

Text("Content")
    .foregroundColor(textColor)

Dark Mode

Support both light and dark appearances.

Automatic Support

// Use semantic colors (automatic)
Color(.label)                // Adapts automatically
Color(.systemBackground)     // Adapts automatically

Testing Dark Mode

// Preview both modes
struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
            .preferredColorScheme(.light)

        ContentView()
            .preferredColorScheme(.dark)
    }
}

Dark Mode Guidelines

Do:

• ✅ Use semantic colors
• ✅ Test with Increase Contrast
• ✅ Test with Reduce Transparency
• ✅ Ensure sufficient contrast in both modes

Don't:

• ❌ Use pure black (#000000) - use systemBackground
• ❌ Invert colors automatically
• ❌ Assume user preference

SF Symbols

Apple's icon system (3000+ symbols).

// Basic symbol
Image(systemName: "heart")

// Colored symbol
Image(systemName: "heart.fill")
    .foregroundColor(.red)

// Sized symbol
Image(systemName: "heart")
    .imageScale(.large)

// Font-based sizing
Image(systemName: "heart")
    .font(.title)

// Multicolor symbols
Image(systemName: "person.crop.circle.fill.badge.checkmark")
    .symbolRenderingMode(.multicolor)

// Hierarchical rendering
Image(systemName: "heart.fill")
    .symbolRenderingMode(.hierarchical)
    .foregroundColor(.red)

SF Symbols Guidelines

• Use system symbols when available
• Maintain visual weight consistency
• Use multicolor for semantic meaning
• Size appropriately for context

App Icons

Icon Sizes

iOS:
- 1024x1024 (App Store)
- 180x180 (iPhone @3x)
- 120x120 (iPhone @2x)
- 167x167 (iPad Pro)
- 152x152 (iPad @2x)

watchOS:
- 1024x1024 (App Store)
- 196x196 (49mm)
- 216x216 (45mm)

Icon Design Guidelines

Do:

• ✅ Use simple, recognizable shapes
• ✅ Fill entire icon space
• ✅ Test on device (not just mockups)
• ✅ Use consistent visual style

Don't:

• ❌ Include text (very small)
• ❌ Use photos
• ❌ Replicate Apple hardware
• ❌ Use translucency

Animation and Motion

Standard Animations

// Spring animation (natural, bouncy)
withAnimation(.spring()) {
    offset = 100
}

// Linear animation
withAnimation(.linear(duration: 0.3)) {
    opacity = 0
}

// Ease in/out
withAnimation(.easeInOut(duration: 0.3)) {
    scale = 1.2
}

Gesture-Driven

@State private var offset = CGSize.zero

var body: some View {
    Circle()
        .offset(offset)
        .gesture(
            DragGesture()
                .onChanged { value in
                    offset = value.translation
                }
                .onEnded { _ in
                    withAnimation(.spring()) {
                        offset = .zero
                    }
                }
        )
}

Motion Guidelines

• Keep animations under 0.3 seconds
• Use spring animations for interactive elements
• Respect Reduce Motion setting
• Provide visual feedback for all interactions

Best Practices

Navigation

• Hierarchical - Use NavigationStack for drilldown
• Flat - Use TabView for peer destinations
• Content-Driven - Use for media apps

Feedback

• Visual - Highlight on tap
• Haptic - Use UIImpactFeedbackGenerator
• Audio - Use system sounds sparingly

Loading States

struct LoadingView: View {
    var body: some View {
        VStack {
            ProgressView()
                .scaleEffect(1.5)
            Text("Loading...")
                .font(.caption)
                .foregroundColor(.secondary)
                .padding(.top)
        }
    }
}

Error States

struct ErrorView: View {
    let message: String
    let retry: () -> Void

    var body: some View {
        VStack(spacing: 16) {
            Image(systemName: "exclamationmark.triangle")
                .font(.system(size: 48))
                .foregroundColor(.orange)

            Text("Something went wrong")
                .font(.headline)

            Text(message)
                .font(.subheadline)
                .foregroundColor(.secondary)
                .multilineTextAlignment(.center)

            Button("Try Again") {
                retry()
            }
            .buttonStyle(.borderedProminent)
        }
        .padding()
    }
}

Empty States

struct EmptyStateView: View {
    var body: some View {
        VStack(spacing: 16) {
            Image(systemName: "tray")
                .font(.system(size: 64))
                .foregroundColor(.secondary)

            Text("No Items")
                .font(.title2)

            Text("Your items will appear here")
                .font(.subheadline)
                .foregroundColor(.secondary)

            Button("Add Item") {
                // Action
            }
            .buttonStyle(.borderedProminent)
        }
    }
}

Platform Considerations

iPhone

• Design for various sizes (SE, Pro, Pro Max)
• Support portrait and landscape
• Use safe areas for notch/Dynamic Island
• Consider one-handed use

iPad

• Support multitasking (Split View, Slide Over)
• Use sidebars for navigation
• Adapt to larger screen (don't just scale)
• Consider keyboard shortcuts
• Support external displays

Apple Watch

• Glanceable information
• Large touch targets (>44pt)
• Minimal interaction required
• Use Digital Crown for scrolling
• Support Always-On display

Resources

• Apple HIG Official
• SF Symbols App
• WWDC Videos
• Apple Design Resources

"Design is not just what it looks like and feels like. Design is how it works." - Steve Jobs