Never lose another contact after upgrade or any software failure.
With Contacts Backup you can easily backup entire address book of iPhone,iPad,iPod and restore it on any smartphone, tablet, PC, Mac
This app is easiest way to backup. Just tap on 'backup now' button on main screen wait for iOS to backup your contacts and converts into .vcf file (it may take a while depending on number of contacts) then email it to yourself.
In case you need to retrieve one or multiple contacts from backup, simply open the mail and tap on 'Contacts.vcf' file, iOS will automatically recognize and prompt adding contacts into address book.