--- name: mobile-design-036425128be3 description: "(Mobile-First · Touch-First · Platform-Respectful)" risk: unknown source: community date_added: "2026-02-27" --- # 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) | 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? | ### Score Formula ``` MFRI = (Platform Clarity + Accessibility Readiness) − (Interaction Complexity + Performance Risk + Offline Dependence) ``` **Range:** `-10 → +10` ### Interpretation | 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 | --- ## 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: | 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.** --- ## 3. Mandatory Reference Reading (Enforced) ### Universal (Always Read First) | 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-Specific (Conditional) | 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. --- ## 4. AI Mobile Anti-Patterns (Hard Bans) ### 🚫 Performance Sins (Non-Negotiable) | ❌ 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 | --- ### 🚫 Touch & UX Sins | ❌ 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 | --- ### 🚫 Security Sins | ❌ 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 | --- ## 5. Platform Unification vs Divergence Matrix ``` UNIFY DIVERGE ────────────────────────── ───────────────────────── Business logic Navigation behavior Data models Gestures API contracts Icons Validation Typography Error semantics Pickers / dialogs ``` ### Platform Defaults | 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 | --- ## 6. Mobile UX Psychology (Non-Optional) ### Fitts’ Law (Touch Reality) * Finger ≠ cursor * Accuracy is low * Reach matters more than precision **Rules:** * Primary CTAs live in **thumb zone** * Destructive actions pushed away * No hover assumptions --- ## 7. Performance Doctrine ### React Native (Required Pattern) ```ts const Row = React.memo(({ item }) => ( {item.title} )); const renderItem = useCallback( ({ item }) => , [] ); i.id} getItemLayout={(_, i) => ({ length: ITEM_HEIGHT, offset: ITEM_HEIGHT * i, index: i, })} /> ``` ### Flutter (Required Pattern) ```dart class Item extends StatelessWidget { const Item({super.key}); @override Widget build(BuildContext context) { return const Text('Static'); } } ``` * `const` everywhere possible * Targeted rebuilds only --- ## 8. Mandatory Mobile Checkpoint Before 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. --- ## 9. Framework Decision Tree (Canonical) ``` Need OTA + web team → React Native + Expo High-perf UI → Flutter iOS only → SwiftUI Android only → Compose ``` No debate without justification. --- ## 10. Release Readiness Checklist ### Before Shipping * [ ] Touch targets ≥ 44–48px * [ ] Offline handled * [ ] Secure storage used * [ ] Lists optimized * [ ] Logs stripped * [ ] Tested on low-end devices * [ ] Accessibility labels present * [ ] MFRI ≥ 3 --- ## 11. Related Skills * **frontend-design** – Visual systems & components * **frontend-dev-guidelines** – RN/TS architecture * **backend-dev-guidelines** – Mobile-safe APIs * **error-tracking** – Crash & performance telemetry --- > **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.** --- ## When to Use This skill is applicable to execute the workflow or actions described in the overview. ## Limitations - Use this skill only when the task clearly matches the scope described above. - Do not treat the output as a substitute for environment-specific validation, testing, or expert review. - Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing. --- Source attribution: ASoudy Original project: https://github.com/ASoudy/AGS/blob/cd1d94757d590093507ef8ac26299eab8bc20478/AGAS/plugins/antigravity-awesome-skills-claude/skills/mobile-design/SKILL.md License: MIT License information: https://opensource.org/license/mit Original upstream instructions; downloaded from Mega AI Hub. ## Upstream license notice MIT License Copyright (c) 2026 Antigravity User Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. # Mega AI Hub resource metadata Creator / publisher: ASoudy Original project: https://github.com/ASoudy/AGS/blob/cd1d94757d590093507ef8ac26299eab8bc20478/AGAS/plugins/antigravity-awesome-skills-claude/skills/mobile-design/SKILL.md Attribution basis: Source repository record Fields of work: Design, Development & Engineering, Product Management Roles: Frontend Developer, Mobile Developer, Product Designer, Product Manager, UX Designer Specialties: Mobile Tools: Tool not specified Country applicability: Country not specified Classification basis: Source catalog labels Instruction SHA-256: 9cab9840b580478e7f83af737d3cce581fb3aee0e17d17ae8052ec599e775483