From this video tutorial, you will find it is easy to import contacts (CSV & vCard) from Outlook, Google, Aol Mail, Thunderbird, Incredimail and other address books to iPhone with the help of iPhone Contacts Backup for Mac. This program also works well for iPhone 5 witho iOS 6. Just have a free try on it.
Video Demo:
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iPhone Contacts Backup for Mac
* Backup contacts to Mac via this program and restore them back to your iPhone if needed
* Import/export contacts information from/to other address books like Google Contacts, Yahoo Address Book and etc
* Transfer contacts between multiple phones without limitation like iPhone/Nokia/Blackberry/Android phone/Windows Phone
* Delete any contact information freely, sort all contacts in different categories, save images of contacts to computer
* Backup SMS, iMessage from iPhone/iPod touch/iPad and save them to your Mac
* Export iOS device Messages and save it as Text/HTML file
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