SKILL.md
Mobile Development Skill
Quick Reference
| Platform | Language | Framework | Timeline | Job Market |
|---|---|---|---|---|
| iOS | Swift | SwiftUI | 6-9 mo | High |
| Android | Kotlin | Compose | 6-9 mo | High |
| Cross-Platform | Dart | Flutter | 4-6 mo | Growing |
| Games | C# | Unity | 12-24 mo | Moderate |
Learning Paths
iOS Development
[1] Swift Fundamentals (4-6 wk)
│ └─ Types, optionals, closures, protocols
│
▼
[2] SwiftUI (4-6 wk)
│ └─ Views, modifiers, state, binding
│
▼
[3] Navigation + Data (3-4 wk)
│ └─ NavigationStack, SwiftData/Core Data
│
▼
[4] Networking + Async (2-3 wk)
│ └─ URLSession, async/await, Combine
│
▼
[5] Testing + App Store (2 wk)
└─ XCTest, TestFlight, submission2025 Stack: Swift 5.10 + SwiftUI + SwiftData + Xcode 16
Android Development
[1] Kotlin Fundamentals (4-6 wk)
│ └─ Null safety, coroutines, data classes
│
▼
[2] Jetpack Compose (4-6 wk)
│ └─ Composables, state, effects
│
▼
[3] Architecture (3-4 wk)
│ └─ MVVM, Room, Navigation
│
▼
[4] Networking + DI (2-3 wk)
│ └─ Retrofit, Hilt, Flow
│
▼
[5] Testing + Play Store (2 wk)
└─ JUnit, Espresso, release2025 Stack: Kotlin 2.0 + Jetpack Compose + Room + Hilt
Flutter (Cross-Platform)
[1] Dart Fundamentals (2-3 wk)
│
▼
[2] Flutter Widgets (3-4 wk)
│
▼
[3] State Management (2-3 wk)
│ └─ Riverpod or Bloc
│
▼
[4] Backend Integration (2 wk)
│ └─ Firebase, REST APIs
│
▼
[5] Deploy to Both Stores (1 wk)2025 Stack: Flutter 3.x + Dart 3.x + Riverpod + Firebase
Game Development
[1] Game Basics (4-6 wk)
│ └─ Game loop, input handling
│
▼
[2] Unity/C# Fundamentals (6-8 wk)
│ └─ GameObjects, Components, Scripts
│
▼
[3] Physics + Graphics (4-6 wk)
│ └─ Rigidbody, colliders, shaders
│
▼
[4] Audio + Polish (2-4 wk)
│
▼
[5] Publish (ongoing)
└─ Steam, App Store, Play Store2025 Stack: Unity 6 LTS + C# OR Unreal 5.4 + C++
Platform Decision Tree
Which platform?
│
├─► Apple ecosystem only?
│ └─► iOS (Swift + SwiftUI)
│
├─► Android ecosystem only?
│ └─► Android (Kotlin + Compose)
│
├─► Both platforms?
│ ├─► Performance-critical? → Native for both
│ ├─► Budget/time limited? → Flutter
│ └─► Web developer background? → React Native
│
└─► Making games?
├─► 2D/3D indie → Unity
├─► AAA quality → Unreal
└─► Simple 2D → GodotGame Engine Comparison
| Engine | Market | Language | Learning | Best For |
|---|---|---|---|---|
| Unity | 51% | C# | Medium | Indie, mobile, VR |
| Unreal | 31% | C++/BP | Hard | AAA, high-fidelity |
| Godot | 10% | GDScript | Easy | Indie, 2D |
Troubleshooting
Native vs Cross-platform?
├─► Need platform-specific APIs (HealthKit, ARCore)? → Native
├─► Performance-critical (AR/VR, complex animations)? → Native
├─► Budget or time limited? → Flutter
├─► Team knows JavaScript? → React Native
└─► Starting from scratch? → Flutter (best DX)
Simulator works, device doesn't?
├─► Missing entitlements/capabilities?
├─► Different iOS/Android version?
├─► Network connectivity issues?
└─► Always test on real devices from day 1
App rejected by store?
├─► Read rejection reason carefully
├─► Check App Store Review Guidelines
├─► Most common: metadata issues, crashes, spam
└─► Appeal if unjustifiedCommon Failure Modes
| Symptom | Root Cause | Recovery |
|---|---|---|
| Slow UI | Too many recompositions | Profile, optimize state |
| Memory leaks | Not cleaning up resources | Use lifecycle-aware components |
| App rejected | Guidelines violation | Read guidelines BEFORE building |
| Game stutters | Draw call overhead | Object pooling, LOD, batching |
Portfolio Projects
Mobile (Progressive)
- Todo App - CRUD basics
- Weather App - API integration
- Chat App - Real-time, auth
- Payment App - Stripe, security
Games
- 2D Platformer - Physics basics
- 3D Runner - 3D graphics, particles
- Multiplayer Game - Networking
Next Actions
Specify your target platform for a detailed learning plan.