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