I've tried Googling this and gotten lots of information, most of it confusing and some of it contradictory. So I thought I'd ask some actual people, which is you folks here on DTF.
I have a Droid phone and a Gmail account. I've had various mobile phones over the years, but in the old days I always just stored my contacts on my phone (on the SIM card, presumably) because that's what you did and "the cloud" was not a big thing.
Ever since then, whenever I get a new phone, I have to make sure my contacts and everything are copied to the new phone. This tends to happen when they copy the contents of the SIM card to the new phone. I remember when this didn't always happen.
Anyway, it's gotten to the point where it's a pain in the ass to have contacts on my phone and also through my Gmail account. I've had friends tell me that it's just easier to synch everything to the cloud. Yeah, I'm starting to agree. Whenever a contact gets a new address, I go to update their address in the contact info, and find that I now have both the old and new address. I try to edit the old address, to actually delete it, and it's not there! Apparently I've edited the phone contact but not the cloud contact, or maybe the other way around.
So... the easiest thing to do would be to just synch all phone contacts to the cloud, and do away with phone contacts altogether. As I said up front, I've tried to figure out how to do this, and even tried to actually do it, and nothing seems to work. I turned on the option to automatically sync contacts to Gmail. When I go into Contacts, under Accounts, I still have my Gmail account and my Phone, and they're still separate lists. There are Phone contacts that are not in my Gmail, and vice versa. If I delete a contact off of my Phone, presumably it's gone, since it's not listed under Gmail contacts. And of course the Phone contacts are my oldest contacts, the ones I'd really like to keep.
Do I have to literally enter all new Gmail contacts and delete the corresponding Phone contacts? There are 93 of them. What a pain. There has to be an easier way.