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.
npxskills add sickn33/antigravity-awesome-skills--skill mobile-designLoading…
(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.
Before designing or implementing any mobile feature or screen, assess feasibility.
| Dimension | Question |
|---|---|
| Platform Clarity | Is the target platform (iOS / Android / both) explicitly defined? |
| Interaction Complexity | How complex are gestures, flows, or navigation? |
| Performance Risk | Does this involve lists, animations, heavy state, or media? |
| Offline Dependence | Does the feature break or degrade without network? |
| Accessibility Risk | Does this impact motor, visual, or cognitive accessibility? |
MFRI = (Platform Clarity + Accessibility Readiness)
− (Interaction Complexity + Performance Risk + Offline Dependence)
Range: -10 → +10
| MFRI | Meaning | Required Action |
|---|---|---|
| 6–10 | Safe | Proceed normally |
| 3–5 | Moderate | Add performance + UX validation |
| 0–2 | Risky | Simplify interactions or architecture |
| < 0 | Dangerous | Redesign before implementation |
If any of the following are not explicitly stated, you MUST ask before proceeding:
| Aspect | Question | Why |
|---|---|---|
| Platform | iOS, Android, or both? | Affects navigation, gestures, typography |
| Framework | React Native, Flutter, or native? | Determines performance and patterns |
| Navigation | Tabs, stack, drawer? | Core UX architecture |
| Offline | Must it work offline? | Data & sync strategy |
| Devices | Phone only or tablet too? | Layout & density rules |
| Audience | Consumer, enterprise, accessibility needs? | Touch & readability |
🚫 Never default to your favorite stack or pattern.
| File | Purpose | Status |
|---|---|---|
| mobile-design-thinking.md | Anti-memorization, context-forcing | 🔴 REQUIRED FIRST |
| touch-psychology.md | Fitts’ Law, thumb zones, gestures | 🔴 REQUIRED |
| mobile-performance.md | 60fps, memory, battery | 🔴 REQUIRED |
| mobile-backend.md | Offline sync, push, APIs | 🔴 REQUIRED |
| mobile-testing.md | Device & E2E testing | 🔴 REQUIRED |
| mobile-debugging.md | Native vs JS debugging | 🔴 REQUIRED |
| Platform | File |
|---|---|
| iOS | platform-ios.md |
| Android | platform-android.md |
| Cross-platform | BOTH above |
❌ If you haven’t read the platform file, you are not allowed to design UI.
| ❌ Never | Why | ✅ Always |
|---|---|---|
| ScrollView for long lists | Memory explosion | FlatList / FlashList / ListView.builder |
| Inline renderItem | Re-renders all rows | useCallback + memo |
| Index as key | Reorder bugs | Stable ID |
| JS-thread animations | Jank | Native driver / GPU |
| console.log in prod | JS thread block | Strip logs |
| No memoization | Battery + perf drain | React.memo / const widgets |
| ❌ Never | Why | ✅ Always |
|---|---|---|
| Touch <44–48px | Miss taps | Min touch target |
| Gesture-only action | Excludes users | Button fallback |
| No loading state | Feels broken | Explicit feedback |
| No error recovery | Dead end | Retry + message |
| Ignore platform norms | Muscle memory broken | iOS ≠ Android |
| ❌ Never | Why | ✅ Always |
|---|---|---|
| Tokens in AsyncStorage | Easily stolen | SecureStore / Keychain |
| Hardcoded secrets | Reverse engineered | Env + secure storage |
| No SSL pinning | MITM risk | Cert pinning |
| Log sensitive data | PII leakage | Never log secrets |
UNIFY DIVERGE
────────────────────────── ─────────────────────────
Business logic Navigation behavior
Data models Gestures
API contracts Icons
Validation Typography
Error semantics Pickers / dialogs
| Element | iOS | Android |
|---|---|---|
| Font | SF Pro | Roboto |
| Min touch | 44pt | 48dp |
| Back | Edge swipe | System back |
| Sheets | Bottom sheet | Dialog / sheet |
| Icons | SF Symbols | Material Icons |
Rules:
const Row = React.memo(({ item }) => (
<View><Text>{item.title}</Text></View>
));
const renderItem = useCallback(
({ item }) => <Row item={item} />,
[]
);
<FlatList
data={items}
renderItem={renderItem}
keyExtractor={(i) => i.id}
getItemLayout={(_, i) => ({
length: ITEM_HEIGHT,
offset: ITEM_HEIGHT * i,
index: i,
})}
/>
class Item extends StatelessWidget {
const Item({super.key});
@override
Widget build(BuildContext context) {
return const Text('Static');
}
}
const everywhere possibleBefore writing any code, you must complete this:
🧠 MOBILE CHECKPOINT
Platform: ___________
Framework: ___________
Files Read: ___________
3 Principles I Will Apply:
1.
2.
3.
Anti-Patterns I Will Avoid:
1.
2.
❌ Cannot complete → go back and read.
Need OTA + web team → React Native + Expo
High-perf UI → Flutter
iOS only → SwiftUI
Android only → Compose
No debate without justification.
Final Law: Mobile users are distracted, interrupted, and impatient—often using one hand on a bad network with low battery. Design for that reality, or your app will fail quietly.
This skill is applicable to execute the workflow or actions described in the overview.
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Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).