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antigravityCreative & Media

mobile-design

Mobile-first design and engineering doctrine for iOS and Android apps. Covers touch interaction, performance, platform conventions, offline behavior, and mobile-specific decision-making. Teaches principles and constraints, not fixed layouts. Use for React Native, Flutter, or native mobile apps.

Documentation

Mobile Design System

(Mobile-First · Touch-First · Platform-Respectful)

Philosophy: Touch-first. Battery-conscious. Platform-respectful. Offline-capable. Core Law: Mobile is NOT a small desktop. Operating Rule: Think constraints first, aesthetics second.

This skill exists to prevent desktop-thinking, AI-defaults, and unsafe assumptions when designing or building mobile applications.


1. Mobile Feasibility & Risk Index (MFRI)

Before designing or implementing any mobile feature or screen, assess feasibility.

MFRI Dimensions (1–5)

DimensionQuestion
Platform ClarityIs the target platform (iOS / Android / both) explicitly defined?
Interaction ComplexityHow complex are gestures, flows, or navigation?
Performance RiskDoes this involve lists, animations, heavy state, or media?
Offline DependenceDoes the feature break or degrade without network?
Accessibility RiskDoes this impact motor, visual, or cognitive accessibility?

Score Formula

MFRI = (Platform Clarity + Accessibility Readiness)
       − (Interaction Complexity + Performance Risk + Offline Dependence)

Range: -10 → +10

Interpretation

MFRIMeaningRequired Action
6–10SafeProceed normally
3–5ModerateAdd performance + UX validation
0–2RiskySimplify interactions or architecture
< 0DangerousRedesign before implementation

2. Mandatory Thinking Before Any Work

⛔ STOP: Ask Before Assuming (Required)

If any of the following are not explicitly stated, you MUST ask before proceeding:

AspectQuestionWhy
PlatformiOS, Android, or both?Affects navigation, gestures, typography
FrameworkReact Native, Flutter, or native?Determines performance and patterns
NavigationTabs, stack, drawer?Core UX architecture
OfflineMust it work offline?Data & sync strategy
DevicesPhone only or tablet too?Layout & density rules
AudienceConsumer, enterprise, accessibility needs?Touch & readability

🚫 Never default to your favorite stack or pattern.


3. Mandatory Reference Reading (Enforced)

Universal (Always Read First)

FilePurposeStatus
mobile-design-thinking.mdAnti-memorization, context-forcing🔴 REQUIRED FIRST
touch-psychology.mdFitts’ Law, thumb zones, gestures🔴 REQUIRED
mobile-performance.md60fps, memory, battery🔴 REQUIRED
mobile-backend.mdOffline sync, push, APIs🔴 REQUIRED
mobile-testing.mdDevice & E2E testing🔴 REQUIRED
mobile-debugging.mdNative vs JS debugging🔴 REQUIRED

Platform-Specific (Conditional)

PlatformFile
iOSplatform-ios.md
Androidplatform-android.md
Cross-platformBOTH above

❌ If you haven’t read the platform file, you are not allowed to design UI.


4. AI Mobile Anti-Patterns (Hard Bans)

🚫 Performance Sins (Non-Negotiable)

❌ NeverWhy✅ Always
ScrollView for long listsMemory explosionFlatList / FlashList / ListView.builder
Inline renderItemRe-renders all rowsuseCallback + memo
Index as keyReorder bugsStable ID
JS-thread animationsJankNative driver / GPU
console.log in prodJS thread blockStrip logs
No memoizationBattery + perf drainReact.memo / const widgets

🚫 Touch & UX Sins

| ❌ Never | Why | ✅ Alway