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)

```bash
# 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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