| name | hapo:mobile-development |
| description | Build mobile apps with React Native, Flutter, Swift/SwiftUI, Kotlin/Jetpack Compose. Use for iOS/Android, mobile UX, performance optimization, offline-first, app store deployment. |
| license | MIT |
| user-invocable | true |
| when_to_use | Invoke to build or modify mobile app features and UI. |
| category | frontend |
| keywords | ["mobile","app","ios","android"] |
| argument-hint | [platform] [feature] |
| metadata | {"author":"haposoft","version":"1.0.0"} |
Mobile Development Skill
Production-ready mobile development with modern frameworks, best practices, and mobile-first thinking patterns.
When to Use
- Building mobile applications (iOS, Android, or cross-platform)
- Implementing mobile-first design and UX patterns
- Optimizing for mobile constraints (battery, memory, network, small screens)
- Making native vs cross-platform technology decisions
- Implementing offline-first architecture and data sync
- Following platform-specific guidelines (iOS HIG, Material Design)
- Optimizing mobile app performance and user experience
- Implementing mobile security and authentication
- Testing mobile applications (unit, integration, E2E)
- Deploying to App Store and Google Play
Technology Selection Guide
Cross-Platform Frameworks:
- React Native: JavaScript expertise, web code sharing, mature ecosystem (121K stars, 67% familiarity)
- Flutter: Performance-critical apps, complex animations, fastest-growing (170K stars, 46% adoption)
Native Development:
- iOS (Swift/SwiftUI): Maximum iOS performance, latest features, Apple ecosystem integration
- Android (Kotlin/Jetpack Compose): Maximum Android performance, Material Design 3, platform optimization
See: references/mobile-frameworks.md for detailed framework comparisons
Mobile Development Mindset
The 10 Commandments of Mobile Development:
- Performance is Foundation, Not Feature - 70% abandon apps >3s load time
- Every Kilobyte, Every Millisecond Matters - Mobile constraints are real
- Offline-First by Default - Network is unreliable, design for it
- User Context > Developer Environment - Think real-world usage scenarios
- Platform Awareness Without Platform Lock-In - Respect platform conventions
- Iterate, Don't Perfect - Ship, measure, improve cycle is survival
- Security and Accessibility by Design - Not afterthoughts
- Test on Real Devices - Simulators lie about performance
- Architecture Scales with Complexity - Don't over-engineer simple apps
- Continuous Learning is Survival - Mobile landscape evolves rapidly
See: references/mobile-mindset.md for thinking patterns and decision frameworks
Reference Navigation
Core Technologies:
mobile-frameworks.md - React Native, Flutter, Swift, Kotlin, framework comparison matrices, when to use eachmobile-ios.md - Swift 6, SwiftUI, iOS architecture patterns, HIG, App Store requirements, platform capabilitiesmobile-android.md - Kotlin, Jetpack Compose, Material Design 3, Play Store, Android-specific features
Best Practices & Development Mindset:
mobile-best-practices.md - Mobile-first design, performance optimization, offline-first architecture, security, testing, accessibility, deployment, analyticsmobile-debugging.md - Debugging tools, performance profiling, crash analysis, network debugging, platform-specific debuggingmobile-mindset.md - Thinking patterns, decision frameworks, platform-specific thinking, common pitfalls, debugging strategies
Key Best Practices (2024-2025)
Performance Targets:
- App launch: <2 seconds (70% abandon if >3s)
- Memory usage: <100MB for typical screens
- Network requests: Batch and cache aggressively
- Battery impact: Respect Doze Mode and background restrictions
- Animation: 60 FPS (16.67ms per frame)
Architecture:
- MVVM for small-medium apps (clean separation, testable)
- MVVM + Clean Architecture for large enterprise apps
- Offline-first with hybrid sync (push + pull)
- State management: Zustand (React Native), Riverpod 3 (Flutter), StateFlow (Android)
Security (OWASP Mobile Top 10):
- OAuth 2.0 + JWT + Biometrics for authentication
- Keychain (iOS) / KeyStore (Android) for sensitive data
- Certificate pinning for network security
- Never hardcode credentials or API keys
- Implement proper session management
Testing Strategy:
- Unit tests: 70%+ coverage for business logic
- Integration tests: Critical user flows
- E2E tests: Detox (React Native), Appium (cross-platform), XCUITest (iOS), Espresso (Android)
- Real device testing mandatory before release
Deployment:
- Fastlane for automation across platforms
- Staged rollouts: Internal → Closed → Open → Production
- Mandatory: iOS 17 SDK (2024), Android 15 API 35 (Aug 2025)
- CI/CD saves 20% development time
Quick Decision Matrix
| Need | Choose |
|---|
| JavaScript team, web code sharing | React Native |
| Performance-critical, complex animations | Flutter |
| Maximum iOS performance, latest features | Swift/SwiftUI native |
| Maximum Android performance, Material 3 | Kotlin/Compose native |
| Rapid prototyping | React Native + Expo |
| Desktop + mobile | Flutter |
| Enterprise with JavaScript skills | React Native |
| Startup with limited resources | Flutter or React Native |
| Gaming or heavy graphics | Native (Swift/Kotlin) or Unity |
Framework Quick Comparison (2024-2025)
| Criterion | React Native | Flutter | Swift/SwiftUI | Kotlin/Compose |
|---|
| Stars | 121K | 170K | N/A | N/A |
| Adoption | 35% | 46% | iOS only | Android only |
| Performance | 80-90% native | 85-95% native | 100% native | 100% native |
| Dev Speed | Fast (hot reload) | Very fast (hot reload) | Fast (Xcode Previews) | Fast (Live Edit) |
| Learning Curve | Easy (JavaScript) | Medium (Dart) | Medium (Swift) | Medium (Kotlin) |
| UI Paradigm | Component-based | Widget-based | Declarative | Declarative |
| Community | Huge (npm) | Growing | Apple ecosystem | Android ecosystem |
| Best For | JS teams, web sharing | Performance, animations | iOS-only apps | Android-only apps |
Implementation Checklist
Project Setup:
- Choose framework → Initialize project → Configure dev environment → Setup version control → Configure CI/CD → Team standards
Architecture:
- Choose pattern (MVVM/Clean) → Setup folders → State management → Navigation → API layer → Error handling → Logging
Core Features:
- Authentication → Data persistence → API integration → Offline sync → Push notifications → Deep linking → Analytics
UI/UX:
- Design system → Platform guidelines → Accessibility → Responsive layouts → Dark mode → Localization → Animations
Performance:
- Image optimization → Lazy loading → Memory profiling → Network optimization → Battery testing → Launch time optimization
Quality:
- Unit tests (70%+) → Integration tests → E2E tests → Accessibility testing → Performance testing → Security audit
Security:
- Secure storage → Authentication flow → Network security → Input validation → Session management → Encryption
Deployment:
- App icons/splash → Screenshots → Store listings → Privacy policy → TestFlight/Internal testing → Staged rollout → Monitoring
Platform-Specific Guidelines
iOS (Human Interface Guidelines):
- Native navigation patterns (tab bar, navigation bar)
- iOS design patterns (pull to refresh, swipe actions)
- San Francisco font, iOS color system
- Haptic feedback, 3D Touch/Haptic Touch
- Respect safe areas and notch
Android (Material Design 3):
- Material navigation (bottom nav, navigation drawer)
- Floating action buttons, material components
- Roboto font, Material You dynamic colors
- Touch feedback (ripple effects)
- Respect system bars and gestures
Common Pitfalls to Avoid
- Testing only on simulators - Real devices show true performance
- Ignoring platform conventions - Users expect platform-specific patterns
- No offline handling - Network failures will happen
- Poor memory management - Leads to crashes and poor UX
- Hardcoded credentials - Security vulnerability
- No accessibility - Excludes 15%+ of users
- Premature optimization - Optimize based on metrics, not assumptions
- Over-engineering - Start simple, scale as needed
- Skipping real device testing - Simulators don't show battery/network issues
- Not respecting battery - Background processing must be justified
Performance Budgets
Recommended Targets:
- App size: <50MB initial download, <200MB total
- Launch time: <2 seconds to interactive
- Screen load: <1 second for cached data
- Network request: <3 seconds for API calls
- Memory: <100MB for typical screens, <200MB peak
- Battery: <5% drain per hour of active use
- Frame rate: 60 FPS (16.67ms per frame)
Resources
Official Documentation:
Tools & Testing:
Community:
