SKILL.md
Install the belt CLI skill: npx skills add belt-sh/cli
App Store Screenshots
Create app store screenshots and preview videos via inference.sh CLI.
Quick Start
Requires inference.sh CLI (belt). Install instructions
belt login
Generate a device mockup scene
belt app run falai/flux-dev-lora --input '{
"prompt": "iPhone 15 Pro showing a clean modern app interface with analytics dashboard, floating at slight angle, soft gradient background, professional product photography, subtle shadow, marketing mockup style",
"width": 1024,
"height": 1536
}'
## Platform Specifications
### Apple App Store (iOS)
| Device | Dimensions (px) | Required |
|--------|-----------------|----------|
| iPhone 6.7" (15 Pro Max) | 1290 x 2796 | Required |
| iPhone 6.5" (11 Pro Max) | 1284 x 2778 | Required |
| iPhone 5.5" (8 Plus) | 1242 x 2208 | Optional |
| iPad Pro 12.9" (6th gen) | 2048 x 2732 | If iPad app |
| iPad Pro 11" | 1668 x 2388 | If iPad app |
- Up to **10 screenshots** per localization
- First **3 screenshots** are visible without scrolling (critical)
- Formats: PNG or JPEG (no alpha/transparency for JPEG)
### Google Play Store (Android)
| Spec | Value |
|------|-------|
| Min dimensions | 320 px (any side) |
| Max dimensions | 3840 px (any side) |
| Aspect ratio | 16:9 or 9:16 |
| Max screenshots | 8 per device type |
| Formats | PNG or JPEG (24-bit, no alpha) |
- Feature graphic: 1024 x 500 px (required for featuring)
- Promo video: YouTube URL (optional but recommended)
## The First 3 Rule
**80% of App Store impressions show only the first 3 screenshots** (before the user scrolls). These three must:
1. Communicate the core value proposition
2. Show the best feature/outcome
3. Differentiate from competitors
### Screenshot Gallery Order
| Position | Content | Purpose |
|----------|---------|---------|
| **1** | Hero — core value, best feature | Stop the scroll, communicate what the app does |
| **2** | Key differentiator | What makes you unique vs competitors |
| **3** | Most popular feature | The thing users love most |
| **4** | Social proof or outcome | Ratings, results, testimonials |
| **5-8** | Additional features | Supporting features, settings, integrations |
| **9-10** | Edge cases | Specialized features for niche users |
## Screenshot Styles
### 1. Device Frame with Caption
The standard: device mockup showing the app, caption text above/below.
┌──────────────────────────┐
│ "Track Your Habits │ ← Caption (benefit-focused)
│ Effortlessly" │
│ │
│ ┌──────────────────┐ │
│ │ │ │
│ │ App Screen │ │ ← Actual app UI in device frame
│ │ Content │ │
│ │ │ │
│ │ │ │
│ └──────────────────┘ │
│ │
└──────────────────────────┘
### 2. Full-Bleed UI (No Device Frame)
The app UI fills the entire screenshot. Works for immersive apps.
### 3. Lifestyle Context
The device shown in a real-world context (person holding phone, on desk, etc.).
### 4. Feature Highlight with Callouts
UI screenshot with arrows/circles pointing to specific features.
## Caption Writing
### Rules
- **Max 2 lines** of text
- **Benefit-focused**, not feature-focused
- **30pt+ equivalent** font size (must be readable in store)
### Examples
❌ Feature-focused:
"Push Notification System"
"Calendar View with Filters"
"Data Export Functionality"
✅ Benefit-focused:
"Never Miss a Deadline Again"
"See Your Week at a Glance"
"Share Reports in One Tap"
## Generating Screenshots
### Hero Screenshot (Position 1)
Clean device mockup with hero feature
belt app run falai/flux-dev-lora --input '{
"prompt": "modern iPhone showing a beautiful fitness tracking app with activity rings and workout summary, device floating at slight angle against soft purple gradient background, professional product shot, clean minimal composition, subtle reflection",
"width": 1024,
"height": 1536
}'
### Feature Highlight
Feature callout style
belt app run bytedance/seedream-4-5 --input '{
"prompt": "app store screenshot style, iPhone showing a messaging app with AI writing suggestions highlighted, clean white background, subtle UI callout arrows, professional marketing asset, modern design",
"size": "2K"
}'
### Lifestyle Context
Device in real-world setting
belt app run falai/flux-dev-lora --input '{
"prompt": "person holding iPhone showing a cooking recipe app, kitchen background with ingredients, warm natural lighting, over-the-shoulder perspective, lifestyle photography, authentic feeling",
"width": 1024,
"height": 1536
}'
### Before/After
Split comparison
belt app run infsh/stitch-images --input '{
"images": ["before-screenshot.png", "after-screenshot.png"],
"direction": "horizontal"
}'
## Preview Videos
### Apple App Store
Spec
Value
Duration
15-30 seconds
Orientation
Portrait or landscape (match app)
Audio
Optional (loops silently in store)
Format
H.264, .mov or .mp4
### Google Play
Spec
Value
Source
YouTube URL
Duration
30s-2min recommended
Orientation
Landscape preferred
### Preview Video Structure
Segment
Duration
Content
Hook
0-3s
Show the core outcome/wow moment
Feature 1
3-10s
Demonstrate top feature in action
Feature 2
10-18s
Second key feature
Feature 3
18-25s
Third feature or social proof
CTA
25-30s
End screen with app icon
Generate preview video scenes
belt app run google/veo-3-1-fast --input '{
"prompt": "smooth screen recording style, finger tapping on a modern mobile app interface, swiping between screens showing charts and data visualizations, clean UI transitions, professional app demo"
}'
## Localization
Each language gets its own set of screenshots. Priorities:
Market
Localization Level
Primary markets
Full: new screenshots + translated captions
Secondary markets
Translated captions, same screenshots
Other
English defaults
Key localization markets: English, Japanese, Korean, Chinese (Simplified), German, French, Spanish, Portuguese (Brazilian)
## A/B Testing (Google Play)
Google Play Console supports store listing experiments:
- Test different screenshot orders
- Test with/without device frames
- Test different captions
- Test different color schemes
- Run for 7+ days with 50%+ traffic for significant results
## Common Mistakes
Mistake
Problem
Fix
Settings screen as screenshot
Nobody cares about settings
Show core value, not infrastructure
Onboarding flow screenshots
Shows friction, not value
Show the app in-use state
Too much text
Unreadable in store
Max 2 lines, 30pt+ font
Wrong dimensions
Rejected by store
Use exact platform specs
All screenshots look the same
No reason to scroll
Vary composition and content
Feature-focused captions
Doesn't communicate benefit
"Never Miss a Deadline" > "Push Notifications"
Outdated UI
Looks abandoned
Update screenshots with each major release
No hero screenshot
Weak first impression
Position 1 = your best shot
## Checklist
- Correct dimensions for target platform
- First 3 screenshots communicate core value
- Captions are benefit-focused, max 2 lines
- No onboarding or settings screens
- Preview video is 15-30s with hook in first 3s
- Localized for top markets
- Feature graphic (1024x500) for Google Play
- Screenshots updated for current app version
- A/B test variant prepared
## Related Skills
npx skills add inference-sh/skills@ai-image-generation
npx skills add inference-sh/skills@ai-video-generation
npx skills add inference-sh/skills@image-upscaling
npx skills add inference-sh/skills@prompt-engineering