the one that came with the phone is just that....the data is only saved on the phone. google contacts saves them to the cloud so that when you log in on a new device all of your previous contacts will be there. you can do that within the contacts settings.

 

Open the samsung contacts app
Menu
Manage contacts
Sync contacts
Select the accounts you want to keep in sync
Sync

 

do the sync with whatever contact you will be using. i never worry about my samsung contacts. as long as google contacts are sync'd i'm good to go.

 

If you use the Samsung Phone app then the Samsung contacts app is used to read the database of contacts on your phone. But, you can use third party phone apps which use other software to read the phone contacts eg I use "Drupe" (from playstore) and never actually open the Samsung Phone or Contacts apps. There are, as always, many options.

If you have followed the sync suggestion above and turned on sync for each account, you should not need to go back and sync manually - it should be automatic.