There are a few ways to backup your iPhone contacts to Gmail. You can use iCloud, a USB cable, or a third-party app.
The easiest way to backup your contacts is to use iCloud. iCloudautomatically backs up your contacts every time you connect to a Wi-Fi network.
If you don’t want to use iCloud, you can backup your contacts using a USB cable. Connect your iPhone to your computer and open iTunes. Select your iPhone in the iTunes sidebar, and …