AppMigrationExtension
An app extension you extend to participate in data export and import.
Declaration
protocol AppMigrationExtension : AppExtension, SendableOverview
During migration, the system calls your extension to collect and export its data to the receiving device. On import, the system calls your app extension just after app installation, but before the app is actually launchable.
The protocols specific to import and export operations extend this type, such as ResourcesExportingWithOptions and ResourcesImporting. For your app extension to successfully export or import data in response to a system call, it needs to conform to one or more of these child protocols.