Download Google's Contacts (DGC) is only get contacts from google and write to iPhone or iPad.
Please notice that DGC may ask you how to do when exist local contacts. my suggestion that turn off contacts in settings first, that mean disconnect other sync for your contacts. then clear your exist contacts in your iPhone, DGC will be get contacts from Google, those contacts maybe duplicate else.
On the other hand, DGC may get contacts from other Google account, and saved into yourself, your contacts will grown faster!
Good Luck!Start(Full Image) Sign in from Google.com(Full Image) Allow visit Google's contacts(Full Image) Loading contacts(Full Image) Confirm(Full Image) Downloading photos(Full Image) Saving contacts(Full Image) Congratulation!(Full Image) Update(Full Image)
DGC will found out new or changed contacts from google, then get those into your device.