Comprehensive App Store asset specifications and guidelines for all promotional artwork — app icons, screenshots, app previews, event cards, subscription images, and featuring artwork.
SkillScore55Maintained
Automatic
◆Design & UX Review pack
Last verified 8/18/2026
What it changes
Passed 12 of 22 test cases with the skill, and 9 of 22 without it.
Without skill41%
With skill55%
Checks it passed that the model alone missed
Classifies App Preview videos as optional but recommended supplementary media.
Specifies PNG as the required file format for App Store icon master submissions.
Lists iPhone, iPad, Mac, Apple Watch, Apple TV, and Apple Vision Pro as platform choices.
and 1 more in the full report
4 fixed8 passed either way9 still failing1 broke
Pass-rate lift
+14 pp
Tokens
+17%
Agent turns
0%
Response time
-16%
Model gemini-3.6-flashMeasured 8/18/2026v112 of 22 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 4 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 4
Prompt
I need to generate artwork for our upcoming app release. What platform options should be presented when selecting multi-platform asset requirements?
What was checked, without and with the skill
Checked
Without skill
With skill
Lists iPhone, iPad, Mac, Apple Watch, Apple TV, and Apple Vision Pro as platform choices.
Missed
Passed
case-07 · gemini-3.6-flash · 8/18/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md80 linessingle file
App Store Assets Generator
Generate complete asset specifications, design guidelines, and checklists for all App Store Connect promotional artwork and media.
When This Skill Activates
Use this skill when the user:
Asks about "App Store asset specs" or "screenshot sizes"
Mentions "app preview" video requirements
Wants to know "what images do I need" for App Store
Preparing assets for submission or update
Asks about "featuring artwork" or "subscription images"
Needs a comprehensive asset checklist
Configuration Questions
Ask user via AskUserQuestion:
Which platforms? (multi-select)
iPhone
iPad
Mac
Apple Watch
Apple TV
Apple Vision Pro
What assets do you need?
App icon
Screenshots
App preview video
In-App Event card images
Subscription promotional images
Custom Product Page assets
All of the above
Output Format
Read specs-reference.md and generate a customized asset checklist for the user's platforms.
AttributedString patterns for rich text formatting, alignment, selection, and SwiftUI integration. Use when working with styled text, text editing, or AttributedString APIs.