What are UTImportedTypeDeclarations and UTExportedTypeDeclarations used for on iOS?

Question

Am I facing a typo here or do really both variations exist on iOS:

• UTImportedTypeDeclarations
• UTExportedTypeDeclarations

Answer 1

You use UTExportedTypeDeclarations if your app defines new UTIs. This tells the system of your own custom UTIs.

You use UTImportedTypeDeclarations if your app uses UTIs created by others but aren't defined by the system.