101-skills 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:
- Communicate the core value proposition
- Show the best feature/outcome
- 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
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