I'm struggling to come up with a rational scheme for managing sync between my mac laptop, my iphone, and google. My corporate center is google apps, so I need to start with contacts from there. However, somehow, I constantly end up with some sync process creating extra copies of my contacts.
I do not have any contact syncing enabled in itunes.
One possible source of distress is that I have two different google accounts: personal and business. The personal account is set to sync contacts via an 'Account' of type 'Exchange', the work ones come in via a card-dav account (I think, the phone doesn't actually tell you what these things are once they exist).
Best Answer
You can easily find out where the duplicate contacts come from by going to your Contacts app on your iPhone and tapping on Groups. Then uncheck your Exchange account and see whether the duplicates persist.
If you are sure that there are no common shared contacts between your personal and your business accounts (Exchange vs CardDAV), I would suppose the duplication comes at the Mac sync stage.
See this for difference between syncing with CardDAV and Exchange.
It is true, however, that once shown on your iPhone, you cannot tell the difference between the two just by looking at the contact entry.