The more detailed explanation is as follows:
I use GMail a lot and have many contacts saved on my gmail.
I also have roughly 400 contacts (phone numbers only) saved on my HTC One.
What's the best way for me to sync the two? Some of the GMail contacts are also contacts on my phone.
I tried playing around with the sync options but ended up transfering ALL past e-mailed contacts to my phone. For example, I've e-mailed college professors 5 years ago one time about class and somehow their e-mails were synced to my phone as new contacts. It was a mess to clean that all up. And how would I prevent future e-mailed contacts from being saved to my phone?
At the moment the phonebook on my HTC One is set to only display contacts from my phone itself (so I don't see the contacts from GMail).