You can get this app free here

By using this app you can backup your contacts by upload to box, dropbox, google drive and gmail through the ‘Contacts Backup‘ app and there is no need to download extra clouds app for contacts backup.

User can simply backup all contacts to a single file for importing to other devices.

Backup supports vCard, Gmail format, Outlook format standard and Microsoft Excel.
Features:
• Added auto contacts backup notification repeat 7,15,30 and 45 days
• All Contacts: shows all contacts in iPhone/iPad memory
• Backup: function support Outlook, Gmail, Microsoft excel, .csv and vCard format needed for almost all devices deal with contacts.
• Restore: function can import/restore contacts.
• Duplicate: function remove duplicate contacts by name or number
• Delete All Contacts: function delete all contacts stored in phone memory
Merge Contacts:
* Shows duplicate contacts with count, based on option selected in options
* On Clicking Duplicate Name, all contacts which have same name will be linked into one contact. User can unlink anytime later. User can merge manually or this app does automatic.
* On Clicking Duplicate Number, it shows the list of duplicates phone number where each contact can be seen on clicking. User can merge manual or automatic.
* On merge, all the contacts will be merged.

Important Notes:
1. In case of Merge Contacts by Option Phone Number, all the contacts who have same phone number will merge into one contact name. Example: a user has had many colleagues/friends who all have same company phone number, this app will link them all into one contact.*If you need help regarding this iPhone application. Write down your comments OR question, developer will answer in this blog.