juanmarchetto/agent-skills/app-store-screenshots

App Store Screenshots

Create app store screenshots and preview videos via inference.sh CLI.

Quick Start

Requires inference.sh CLI (infsh). Get installation instructions: npx skills add inference-sh/skills@agent-tools

infsh login
 
# Generate a device mockup scene
infsh 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)

• 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)

• 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

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

Bad (feature-focused):
"Push Notification System"
"Calendar View with Filters"
"Data Export Functionality"
 
Good (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
infsh 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
infsh 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
infsh 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
infsh app run infsh/stitch-images --input '{
  "images": ["before-screenshot.png", "after-screenshot.png"],
  "direction": "horizontal"
}'

Preview Videos

Apple App Store

Google Play

Preview Video Structure

# Generate preview video scenes
infsh 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:

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

Important

AI-generated images (via inference.sh) produce marketing mockups, not real app screenshots. For actual screenshots of your running app, use maestro-mobile-testing or playwright-recording to capture real screens, then use this skill for framing, captions, and store optimization.

Example Output

App Store Screenshot Set Generated:
- hero-iphone15pro.png (1290x2796) — "Track Your Habits Effortlessly"
- feature-calendar.png (1290x2796) — "See Your Week at a Glance"
- social-proof.png (1290x2796) — "Join 50,000+ Users"
- ipad-pro.png (2048x2732) — "Beautiful on Every Screen"
- feature-graphic.png (1024x500) — Google Play feature graphic

Error Handling

• Wrong dimensions: Check platform specs table above — App Store and Play Store have different requirements
• Store rejection: Common causes: transparency in JPEG (use PNG), text too small (30pt+ minimum), screenshots show non-final UI
• AI mockup looks generic: Add specific details to the prompt (your app's actual color scheme, specific screen content, real feature names)

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

Browse all apps: infsh app list