Apple provide a really helpful and in depth guidance around Marketing Resources and Identity Guidelines for your app when it is to be published on their app store.
These resources include guidance and downloadable files for the following –
App Store Badges
Product Images
Photography + Video
Messaging + Style
Legal Requirements
Apple also provide custom app specific content for your use, using the Apple Media Services Tools page.
To get to this page you can visit the following url – https://tools.applemediaservices.com/app-store/ and search for your application using the search box and then choosing it from the result(s) that appear below in the apps section.
This page will share with you your App Store URL, a Short Link Generator, the App Icon, Embed Code for Apple Badges, Download Link for your Apple Badges, and finally the ability to generate a QR Code for your app on the App Store.
If for some reason you are not able to find your App using the search function, you can use the below url, just replacing the text ‘APP ID’ with your App ID that is visible inside your App Store Connect account.
Here’s the link – https://tools.applemediaservices.com/app/APPID