Follow steps below:
How to Sync Contacts between iPhone and Gmail1. Launch Gmail and connect your device to the computer. Transfer your iPhone contacts to Gmail in the form of vCard file.
2. Go to "Settings" on your iPhone and tap on "Mails, Contacts, Calendars".
3. Select "Add account" and tap on "Exchange" afterwards.
4. Enter your full Google Account email address, username and password in the interface.
5. Click "Accept" in the pop-up window and you'll get an interface shown right below.
6. Input "m.google.com" in the "Server" box.
7. Select the services you'd like to sync. Turn on contacts so you can sync Gmail contacts to your device now. Select the "Keep on my iPhone" option when prompted if you would like to keep your existing contacts on your device. That will allow you to keep duplicate contacts on your device.
8. Return to "Mails, Contacts, Calendars" and select "Contacts" and you'll find "Groups" newly displayed on the top left corner.
9. Press "Groups" option to get the window below. "All Contacts" are the ones on your Gmail and iPhone contacts.
These 9 simple steps will lead you to sync iPhone contacts with Gmail successfully now. You won't need to input all those contacts on Gmail to your iPhone one by one any more. Besides, this method works for all iOS devices such as iPad or iPod touch.
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