iOS Development

Start here. This skill coordinates the Apple skills collection — it tells you which skill to use and when, so you get opinionated guidance and full API references together.

Operating Rules

SwiftUI and UIKit are both first-class — pick whichever fits the task. UIKit is a valid choice whenever it gives more control or flexibility; when bridging the two, watch state sync, lifecycle, and animation/environment boundaries.
Do not enforce specific architectures (MVVM, VIPER, MV, TCA, etc.) — encourage separating business logic from views without mandating how
Hold a high bar for UI craft: apps should feel current-generation — fluid, design-forward, alive. Sweat the tiny details. Custom components, novel interactions, and custom Metal shaders are all in-bounds when they serve the experience; system defaults are a floor, not a ceiling.
Do not prescribe how that craft is delivered — no house style, no "Apple-approved" gatekeeping, no aesthetic checklists. Design direction is your own judgment call, made per app. The
```
hig
```
and
```
ios-liquid-glass
```
skills document what the system provides; they are references, not style mandates. When the task is designing a screen or making it look good, there is no doc to route to — design from your own taste; grep references only when you need API mechanics or a factual minimum (e.g. hit-target sizes).
Present performance optimizations as suggestions backed by reasoning, not blanket requirements
When you need exact API details, grep the framework reference skills — they contain full Apple documentation

Task Workflows

Review existing code

Read the code and identify which topics apply
Run the Correctness Checklist below — violations are bugs
Use the Topic Router to load the relevant guide for each topic
For API correctness, grep the matching framework reference skill

Improve existing code

Run the correctness checklist first
For performance issues: use
```
guide-swiftui-performance-audit
```
For navigation, state, or pattern questions: use
```
guide-swiftui-ui-patterns
```
For API details: grep the matching framework reference skill

Build a new feature

Design data flow first — identify owned vs. injected state
For UI patterns and app wiring: use
```
guide-swiftui-ui-patterns
```
For API details: grep the matching framework reference skill
Structure views for optimal diffing — extract subviews early
Run the correctness checklist before finishing

Topic Router

The Guide column has opinionated, short pattern guides. The API Reference column has full Apple documentation as grepable Markdown — use

apple-docs-index

to find which framework has what.

Topic	Guide	API Reference
State management	`guide-swiftui-ui-patterns`	`swiftui` (state.md, binding.md, observation.md, environment.md)
View composition	—	`swiftui` (view-protocol.md)
Performance	`guide-swiftui-performance-audit`	—
Navigation	`guide-swiftui-ui-patterns`	`swiftui` (navigationstack.md, navigationsplitview.md, navigationlink.md)
Sheets & modals	`guide-swiftui-ui-patterns`	`swiftui` (sheet.md, inspector.md, alert.md, confirmationdialog.md)
Lists & ForEach	`guide-swiftui-ui-patterns`	`swiftui` (list.md)
ScrollView	`guide-swiftui-ui-patterns`	`swiftui` (scrollview.md)
Forms & input	—	`swiftui` (form.md, textfield.md, picker.md, toggle.md, slider.md)
Charts	`guide-swiftui-charts`	`swiftui` (chart.md, charts-overview.md)
Animations	`guide-swiftui-animations`	`swiftui` (swiftui-overview.md)
Layout	`guide-swiftui-ui-patterns`	`swiftui` (geometryreader.md, grid.md, hstack.md, vstack.md, zstack.md, spacer.md)
TabView	`guide-swiftui-ui-patterns`	`swiftui` (tabview.md)
Liquid Glass	—	`ios-liquid-glass`
Accessibility	`guide-swiftui-ui-patterns`	`hig` (a11y/ergonomic facts)
macOS apps	`guide-macos-spm-packaging`	`swiftui` , `uikit`
Data persistence	`guide-swiftdata`	`swiftdata`
Testing	`guide-swift-testing`	`swift-testing` , `xcuitest`
Concurrency	`guide-swift-concurrency`	`swift-concurrency`
In-app purchases	—	`storekit`
Maps	—	`mapkit`
Health data	—	`healthkit`
Notifications	—	`usernotifications`
App Intents / Siri	—	`appintents`
Widgets	—	`widgetkit`
App Store metadata	`apple-aso`	—
Finding docs	`apple-docs-index`	—

Correctness Checklist

These are hard rules — violations are always bugs:

```
@State
```
properties are
```
private
```
```
@Binding
```
only where a child needs to mutate parent state
Values passed in are never declared as
```
@State
```
— they silently ignore updates

Use

@State

with

@Observable

classes — not

@StateObject

ObservableObject

Use
```
@Bindable
```
for injected observables that need bindings
```
ForEach
```
uses stable identity — never
```
.indices
```
on dynamic content
Each
```
ForEach
```
element produces a constant number of views
```
.animation(_:value:)
```
always includes the
```
value:
```
parameter
```
@FocusState
```
properties are
```
private
```
```
@Observable
```
classes are
```
@MainActor
```
— Swift 6 strict concurrency requires it
Property wrappers (
```
@AppStorage
```
,
```
@SceneStorage
```
,
```
@Query
```
) inside
```
@Observable
```
classes are marked
```
@ObservationIgnored
```
— they conflict with the macro and cause compiler errors
No business logic in
```
body
```
— use
```
.task
```
,
```
.onChange
```
, or methods
No
```
AnyView
```
unless truly unavoidable — fix with better composition

Related Skills

System API reference:

```
/ios-liquid-glass
```
— Liquid Glass API reference

Workflow guides:

```
/guide-swiftui-ui-patterns
```
— Navigation, state, sheets, component patterns
```
/guide-swiftui-animations
```
— Implicit/explicit animation, transitions, keyframes
```
/guide-swiftui-charts
```
— Marks, axes, selection, styling, accessibility
```
/guide-swiftui-performance-audit
```
— Diagnose and fix performance issues
```
/guide-swift-testing
```
— Swift Testing patterns, async tests, common agent mistakes
```
/guide-swift-concurrency
```
— Concurrency patterns, actors, diagnostics, bug patterns
```
/guide-swiftdata
```
— SwiftData patterns, predicates, CloudKit constraints
```
/guide-macos-spm-packaging
```
— Build macOS apps with SwiftPM

Utilities:

```
/apple-docs-index
```
— Find the right Apple documentation
```
/simulator-utils
```
— Simulator screenshots and device management
```
/apple-aso
```
— App Store Optimization

ios-dev

NPX Install

Tags

SKILL.md Content