vCard Editor is the application for viewing and editing vCard files.
When you receive a vCard via Email or AirDrop etc, you can send it to vCard Editor instead of iOS Contacts app, and check and modify it, then export it to your Contacts or save it in the iCloud Drive as a file.
Also you can use vCard Editor not only for viewing and editing vCard but also for a private AddressBook.
And using embedded vCard Extention, you can export a contact to merge it to the other vCard file.