Overview
Every app and model in the Thumper-Run catalog needs visual assets. Well-prepared assets make your listing look professional, help users find your app, and ensure consistent rendering across the catalog, social sharing, and in-app cards.
This page specifies the exact dimensions, formats, and requirements for each asset type. Follow these specs to avoid rejection during the publishing review process.
Emoji & Icon
Each manifest includes an emoji field for quick visual identification and an optional icon for higher-fidelity display.
| Field | Format | Dimensions | Example |
|---|---|---|---|
| emoji | Single Unicode character | N/A | one pictograph (legacy; prefer icon) |
| icon | PNG (transparent background preferred) | 256×256 px | icon.png in manifest directory |
Icon Guidelines
- Use a transparent background so the icon works on any card color
- Keep the subject centered with some padding (the icon may be displayed at 48×48 or 64×64)
- Avoid text in the icon — it will be unreadable at small sizes
- If no icon is provided, the emoji is used as the fallback
Screenshots
Screenshots are the primary way users evaluate your app before installing. High-quality screenshots significantly improve install rates.
| Requirement | Value |
|---|---|
| Minimum resolution | 1280×720 px |
| Aspect ratio | 16:9 |
| Count | 3–5 required for catalog listing |
| Formats | PNG or JPEG |
| Max file size | 2 MB per image |
Good Screenshots
- Show the app in action with real output (not placeholder content)
- Capture the full window at native resolution — avoid scaling artifacts
- Include at least one screenshot of the main workflow
- Show different features across screenshots (don’t repeat the same view)
Bad Screenshots
- Cropped or low-resolution captures
- Screenshots of loading screens or error states
- Images with personal data, API keys, or file paths visible
- Non-16:9 aspect ratios (will be letterboxed in the catalog)
Cover Image
The cover image is used for social sharing (Open Graph) and as the hero image on catalog detail pages. It appears when your app’s link is shared on Twitter, Discord, Slack, etc.
| Requirement | Value |
|---|---|
| Dimensions | 1200×630 px |
| Format | PNG or JPEG |
| Max file size | 1 MB |
| Content | App name + representative visual; avoid small text |
Gradients
Each manifest can specify Tailwind CSS gradient classes for card backgrounds in the catalog. These gradients appear on app cards, model cards, and as fallback when no cover image is set.
| Field | Example Value | Appears In |
|---|---|---|
| gradient_from | from-purple-600 | Card backgrounds, cover fallback |
| gradient_to | to-blue-500 | Card backgrounds, cover fallback |
| gradient_via (optional) | via-indigo-500 | Three-stop gradients for richer color |
Choose gradient colors that complement your app’s branding. The catalog renders gradients as bg-gradient-to-br (bottom-right direction) by default.
Checklist
Use this quick reference to ensure you have all required assets before publishing.
| Asset | App Manifest | Model Manifest | Pack Manifest |
|---|---|---|---|
| emoji | Required | Required | Required |
| icon (256×256) | Recommended | Recommended | Recommended |
| screenshots (3–5) | Required | N/A | Recommended |
| cover image (1200×630) | Recommended | Recommended | Recommended |
| gradient classes | Required | Required | Required |
Key Takeaways
- Icon: 256×256 PNG with transparent background
- Screenshots: 1280×720 minimum, 16:9, 3–5 per app
- Cover image: 1200×630 for social sharing (Open Graph)
- Gradient classes are required for all manifest types