Integration guides.

The studio's export layout picker writes the rendered bundle in a tree that drops directly into your repo. One row below per supported project shape:

The default (raw / flat) layout produces theme/size/lang/n.png and is intended for web pages, social, and decks rather than store submission.

Flutter projects keep iOS and Android in subdirs, each with its own fastlane/.

cd /path/to/your_flutter_app
unzip ~/Downloads/appscreen-*.zip

Files land at:

ios/fastlane/screenshots/<locale>/iPhone69/01.png …
android/fastlane/metadata/android/<locale>/images/phoneScreenshots/01.png …

Append a screenshots lane to ios/fastlane/Fastfile and android/fastlane/Fastfile (snippets in the Fastfile lanes section), then run:

cd ios && bundle exec fastlane screenshots && cd ..
cd android && bundle exec fastlane screenshots && cd ..

Same layout as Flutter — separate ios/ + android/ subprojects each with their own fastlane folder. Expo bare-workflow projects follow the same shape after expo prebuild.

cd /path/to/your_rn_app
unzip ~/Downloads/appscreen-*.zip

cd ios && bundle exec fastlane screenshots && cd ..
cd android && bundle exec fastlane screenshots && cd ..

Capacitor's iOS xcworkspace lives under ios/App/. Files land at ios/App/fastlane/ + android/fastlane/.

cd /path/to/your_capacitor_app
unzip ~/Downloads/appscreen-*.zip

cd ios/App && bundle exec fastlane screenshots && cd ../..
cd android  && bundle exec fastlane screenshots && cd ..

KMM projects use iosApp/ + androidApp/ modules.

cd /path/to/your_kmm_app
unzip ~/Downloads/appscreen-*.zip

cd iosApp     && bundle exec fastlane screenshots && cd ..
cd androidApp && bundle exec fastlane screenshots && cd ..

For a repo with fastlane initialised at the project root — either an Xcode-only iOS project or a Gradle-only Android project. The bundle's fastlane/ folder merges with the existing one.

cd /path/to/your_project
unzip ~/Downloads/appscreen-*.zip

# iOS
bundle exec fastlane screenshots

# Android
bundle exec fastlane screenshots

One-time setup of an App Store Connect API key (recommended over login + 2FA prompts) and, for Play Store, a Google service account.

App Store Connect API key

1. App Store Connect → Users and Access → Integrations → App Store Connect API → Generate API Key. Role: Marketing (sufficient for screenshots; least privilege).
2. Download the .p8 private key. Note the Key ID and Issuer ID.
3. Save the key to ~/.appstore/AuthKey.p8 and create an ~/.appstore/api_key.json:

{
  "key_id": "ABC1234XYZ",
  "issuer_id": "00000000-0000-0000-0000-000000000000",
  "key_filepath": "~/.appstore/AuthKey.p8"
}

Google Play service account

1. Google Cloud Console → create a service account in the project linked to your Play account. Grant role Service Account User.
2. Generate a JSON key for that service account. Save as ~/.playstore/service-account.json (and gitignore it if committing fastlane config).
3. Play Console → Users and permissions → invite the service-account email. Grant Manage store presence.

Append these lanes to the appropriate Fastfile (see the layout table for the path).

iOS

# inside platform :ios do … end
desc "Upload screenshots only"
lane :screenshots do |options|
  project_root = File.expand_path("..", __dir__)
  api_key_path = options[:api_key_path] ||
                 ENV["APP_STORE_CONNECT_API_KEY_PATH"] ||
                 File.expand_path("~/.appstore/api_key.json")

  api_key = app_store_connect_api_key(
    key_id:       JSON.parse(File.read(api_key_path))["key_id"],
    issuer_id:    JSON.parse(File.read(api_key_path))["issuer_id"],
    key_filepath: JSON.parse(File.read(api_key_path))["key_filepath"],
    duration:     1200,
  )

  deliver(
    api_key:               api_key,
    skip_binary_upload:    true,
    skip_metadata:         true,
    skip_screenshots:      false,
    overwrite_screenshots: true,
    force:                 true,
    screenshots_path:      File.join(project_root, "fastlane", "screenshots"),
  )
end

Android

# inside platform :android do … end
desc "Upload screenshots only"
lane :screenshots do
  upload_to_play_store(
    skip_upload_apk:         true,
    skip_upload_aab:         true,
    skip_upload_metadata:    true,
    skip_upload_changelogs:  true,
    skip_upload_images:      false,
    skip_upload_screenshots: false,
    metadata_path:           File.expand_path("./metadata", __dir__),
  )
end

The bundle is just files; any CI flow that already runs fastlane can pull it during a release build. Two common patterns:

1. Manual checkout: download the ZIP from AppScreen, commit fastlane/screenshots and fastlane/metadata, run fastlane in CI on tag push.
2. Stored in CI artifact: upload the ZIP to your CI artifact store; expand into fastlane/ before the lane runs. Useful if you don't want generated PNGs in version control.

Example GitHub Actions step:

- name: Unzip AppScreen bundle
  run: |
    unzip -q appscreen-bundle.zip -d .
- name: Publish screenshots
  env:
    ASC_KEY_ID:    ${{ secrets.ASC_KEY_ID }}
    ASC_ISSUER_ID: ${{ secrets.ASC_ISSUER_ID }}
    ASC_KEY_PATH:  ${{ secrets.ASC_KEY_PATH }}
  run: bundle exec fastlane screenshots

Render every language you support inside one bundle (each maps to the correct en-US, es-ES, de-DE folder). Fastlane pushes them all in one run, but each locale must already be added to the editable version in App Store Connect / Play Console — otherwise it gets silently skipped.

1. Asset failed validation on iOS: typically a non-RGB / alpha-channel PNG. AppScreen's fastlane export already alpha-flattens for store layouts, so this only happens if you swapped a manual file in. Re-render the bundle.
2. 401 INVALID_PROVIDER from supply: the service account isn't invited in Play Console yet, or its role is too narrow. Add Manage store presence.
3. Wrong device folder: deliver expects iPhone69 / iPhone67 / iPhone65. The export uses these names already.
4. Empty Media Manager after a successful upload: you're probably viewing the inflight (locked) version. Open the version in Prepare for Submission; that's where deliver writes.