---
name: android-to-ios
description: Use Android/Kotlin code as the source of truth and implement the equivalent feature in iOS/Swift. Understands the feature behavior, data structures, and logic from Android, then creates idiomatic iOS code that matches the target codebase's existing patterns. Use when porting features from Android to iOS or ensuring platform consistency.
---

# Android to iOS: Feature Parity Implementation

Use Android code as the reference to implement the equivalent iOS feature. Not a literal translation - understand what the Android code does, then implement it idiomatically for iOS.

**Use this when:**
- Porting a feature from Android to iOS
- Android is the "source of truth" for a feature
- Ensuring feature parity between platforms

## Key Principle

```
Android Code → Understand Feature → Match iOS Codebase Patterns → Implement
                  (what)                  (how it's done here)
```

**Preserved:** Feature behavior, data structure shapes, business logic, user flows
**Adapted:** Language idioms, frameworks, patterns to match the iOS codebase

---

## Workflow

### Step 0: Gather Context

**Ask the user for both pieces of information:**

```
To port a feature from Android to iOS, I need:

1. PATH TO ANDROID CODEBASE (source of truth)
   Where is the Android project located?
   Example: /path/to/android-app or ../android-app

2. FEATURE TO IMPLEMENT
   What feature or component should I port?
   Example: "UserProfile screen" or "the authentication flow" or "app/src/main/java/features/checkout"
```

**Assumptions:**
- Current working directory = iOS codebase (target)
- User provides path to Android codebase (source)

If the user already provided this info, proceed. Otherwise, ask.

### Step 1: Locate the Android Feature

Navigate to the Android codebase path and find the relevant files:

1. Go to the Android path provided
2. Find files related to the feature
3. Read and understand the implementation

### Step 2: Analyze the Android Code

Thoroughly understand:

| Aspect | What to Extract |
|--------|-----------------|
| **Feature Behavior** | What does this feature do? User-facing functionality |
| **Data Structures** | Models, types, sealed classes - their shapes and relationships |
| **Business Logic** | Core logic, validations, transformations |
| **State Management** | What state exists, how it flows |
| **API Contracts** | Network calls, request/response shapes |
| **UI Flow** | Screens, navigation, user interactions |
| **Edge Cases** | Error handling, loading states, empty states |

```
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                  ANDROID FEATURE ANALYSIS
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

## Feature: [Name]

### What It Does
[User-facing description]

### Data Structures
[Key models and their relationships]

### Business Logic
[Core logic summary]

### State
[What state is managed, how it changes]

### API Calls
[Endpoints, request/response shapes]

### UI Flow
[Screens, navigation]

### Edge Cases Handled
- [Case 1]
- [Case 2]

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
```

### Step 3: Analyze iOS Codebase Patterns

**Before implementing, understand how THIS iOS codebase does things:**

1. **Check if `.claude/codebase-style.md` exists** - If yes, use it and skip manual analysis
2. Find similar features in the codebase
3. Note the patterns used:
   - Architecture pattern
   - UI framework and patterns
   - State management approach
   - Networking approach
   - Dependency injection
   - File/folder organization
   - Naming conventions

```
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                 iOS CODEBASE PATTERNS
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Style Guide: [Found / Not found]

Patterns observed from existing code:
- Architecture: [what pattern is used]
- UI: [how UI is built]
- State: [how state is managed]
- Networking: [how API calls are made]
- DI: [how dependencies are injected]
- Navigation: [how navigation works]

Similar features to reference:
- [Feature 1]: [path]
- [Feature 2]: [path]

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
```

### Step 4: Create Implementation Plan

Map the Android feature to iOS equivalents **using the patterns from Step 3**:

```
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                  IMPLEMENTATION PLAN
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

## Files to Create

| # | File | Purpose | Android Equivalent |
|---|------|---------|-------------------|
| 1 | [path matching codebase conventions] | [purpose] | [Android file] |
| 2 | ... | ... | ... |

## Key Mappings

| Android Concept | iOS Equivalent (matching codebase patterns) |
|-----------------|---------------------------------------------|
| [Android thing] | [iOS equivalent as done in this codebase] |
| ... | ... |

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
```

### Step 5: Implement

Create the iOS implementation:

- **Match the codebase's existing patterns exactly**
- Use the same architecture, UI patterns, state management as other features
- Follow the same naming conventions
- Keep data structure shapes equivalent for API compatibility

**⚠️ IMPORTANT: After creating each `.swift` file, register it with Xcode:**

```bash
ruby ${CLAUDE_PLUGIN_ROOT}/skills/add-to-xcode/scripts/add_to_xcode.rb <filepath>
```

Without this step, files won't appear in Xcode or compile. See the `add-to-xcode` skill.

### Step 6: Copy Assets (if needed)

**If the feature uses assets, offer to copy them:**

Assets that may need to be copied:
- Images, icons, colors, fonts, Lottie animations, sounds, etc.

If assets are needed and the user wants them copied, use file operations to transfer them from the Android codebase to the appropriate iOS locations.

### Step 7: Report Results

```
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                 ANDROID → iOS COMPLETE
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

## Feature: [Name]

### Files Created

| File | Purpose |
|------|---------|
| [path] | [description] |

### Feature Parity Checklist

- [x] Core functionality matches Android
- [x] Data structures equivalent
- [x] Error handling preserved
- [x] Loading states preserved
- [x] Edge cases handled
- [x] Matches iOS codebase patterns

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
```

---

## Triggers

```
"android to ios"
"convert from android"
"port this kotlin to swift"
"implement this android feature for ios"
"ios version of this android code"
```

---

## Integration with style-guide

**Recommended:** Run the `style-guide` skill on the iOS codebase first.

```
style guide     ← Run this first on iOS codebase
android to ios  ← Then run this
```

This generates `.claude/codebase-style.md` which this skill will automatically reference.

**If style guide exists:**
- Skip manual pattern analysis (Step 3)
- Reference the documented patterns directly
- Ensure perfect consistency with existing code

**If no style guide:**
- This skill will analyze patterns manually (Step 3)
- Consider running `style-guide` first for better results

---

## Tips

1. **Don't translate literally** - Understand the feature, then implement idiomatically
2. **Match the codebase** - Use the same patterns as existing iOS code
3. **Keep data shapes equivalent** - API compatibility matters
4. **Handle platform differences** - Some things work differently (lifecycle, permissions)
5. **Verify feature parity** - Same behavior, not same code