Did you just upgrade your iPhone to iOS 6 and you lost your contacts in the process? Is your computer running OS X Mountain Lion? Then we might have a solution for you.
I too upgraded to iOS 6 and then discovered that about half of my contacts were missing, even after syncing with iCloud. This debacle greatly confused me, because since I had just assumed that all of my contacts on my previous iPhone 4S had been all along syncing with iCloud. After doing some troubleshooting, I was relieved to discover that all of my missing contacts were still stored in my Gmail account. After putting two and two together, I realized that my Gmail contacts had never actually been syncing with iCloud. So now that I had located my missing contacts, I had to send them up to iCloud. Here’s how to do just that.
1. First things first, log in to your Gmail / Google mail account and export your contacts:
The Export option can be found under the More button.
Export your contacts in “vCard format”.
2. In Mountain Lion, open the Contacts app.
In the Contacts app, go to File / Import. And import the .vcf file that you exported from your Gmail account.
Once this has been done, if your Mac is set to sync with iCloud, then your contacts should automatically sync up to iCloud, and then down to your iPhone.
3. But wait, there is more!
While you still have the Contacts app loaded. Go to Preferences / Accounts / On My Mac and make sure that the Synchronize with Google box is checked off. From then on, the contacts in your Gmail / Google mail account should automatically be synced with iCloud, and in turn your iPhone (or any other iOS device running iOS 6).