Using UTType in Swift in Xcode 12 and iOS 14 related code from blog post on emptytheory.com at https://emptytheory.com/2020/09/29/better-uniform-type-identifiers-with-xcode-12/

UTTypeiOS14.swift

//https://emptytheory.com/2020/09/29/better-uniform-type-identifiers-with-xcode-12/

import UniformTypeIdentifiers
 
//Show UTType properties for built-in type
UTType.pdf.printInfo()
 
//Show properties for looked up type
UTType.word.printInfo()
 
extension UTType {
    
    /// Show some properties on the UTType
    func printInfo() {
        print("MIME type: \(preferredMIMEType ?? "No MIME Type")")
        print("File Extension: \(preferredFilenameExtension ?? "No extension")")
        print("Tags: \(tags)")
        print("Identifier: \(identifier)")
    }
 
    static var word: UTType {
        UTType.types(tag: "docx", tagClass: .filenameExtension, conformingTo: nil).first!
    }
    
}