development

Bundle Identifier

A unique reverse-domain string (e.g., com.yourcompany.yourapp) that identifies an app across Apple's ecosystem, used for code signing, provisioning, and App Store submission.

app id code signing provisioning profile

The bundle identifier is your app’s unique identifier within Apple’s ecosystem. It follows reverse-domain notation (e.g., com.yourcompany.yourapp) and must be globally unique across all apps on the App Store.

Where the Bundle Identifier Appears

  • In your Xcode project’s target settings
  • In your App ID registration in the Apple Developer portal
  • In your provisioning profiles
  • In your AASA file for Universal Links and App Clips
  • In App Store Connect when creating your app listing

Naming Conventions

  • Use reverse-domain format: com.yourcompany.yourapp
  • App extensions append to the parent: com.yourcompany.yourapp.widget
  • App Clips append .Clip: com.yourcompany.yourapp.Clip
  • Use lowercase letters, numbers, and hyphens only
  • Cannot be changed after your app is published on the App Store

Bundle ID and App Clips

App Clip bundle identifiers must be the parent app’s bundle ID with .Clip appended. This naming hierarchy is enforced by the system and is required for domain verification through AASA files.

Common Issues

  • Bundle ID mismatch: The identifier in Xcode must exactly match the App ID in the Developer portal and the provisioning profile
  • Already taken: If someone else has registered the same identifier, you must choose a different one
  • Extension hierarchy: All extensions must use the parent app’s bundle ID as a prefix