What does the import and export of oppo mobile phones mean? I found the phone number missing? Thank you for your questions.

Import and export in the mobile phone is a function of the phone book. You can export the phone book to a memory card in format. Csv is equivalent to backing up the phone book. You can also import this content when your phone book is accidentally deleted. The csv file is put into the phone book to display the address book. Yes. Csv file can be opened in Excel of computer, which is equivalent to an Excel table.