Gmail is a free, advertising-supported email service provided by Google. Users may access Gmail as secure webmail, as well as via POP3 or IMAP4 protocols. Gmail account also let you add contacts which includes name, email address and telephone number. Here is the instruction to tell you how to update your phone numbers on Gmail.
1. Click on the “Gmail” button on the upper left and click “Contacts” from the drop-down menu. Then you will see your contact book.
2. Locate the contact you want to edit and click “Contact Info.”
3. Enter the contact’s telephone number in the “Phone” field to update his information.
4. Click the right country flag button to the left of the phone number to update the country code for the number.
5. Click the “Mobile” label to change the label of the contact’s phone number.
6. Click “Add Phone” to add additional phone numbers. And you could do the above settings as I just told you.