"App ID" is short form of Application ID. Application ID is an unique application identifier provided by a platform or OS, it is typically defined by the application.
For more information about Android App ID continue to developer.android.com/studio/build/application-id.html.
Bundle ID is used on iOS as a source of App ID.
It removes an access from a specific client (e.g., mobile application) to CatVision.io server.
Product is how we call environment from where you can access mobile devices with your application equipped with CatVision.io SDK. Every application has its own Product, so it is more clear and well-aranged that way. You can have one Product, or ten Products, it depends only on you.