For Cortana to work with Google apps, these apps must first be identified as a service. Access Cortana and click Notebook, and once the panel appears, access Connected Services and from there, Add service.
At this point, you will only be given an option for Gmail, but that includes Contacts and Calendar as well, in addition to Google Drive. After you next sign on to your Google account, your Connected Services menu will include Gmail as an option.
Privacy and Usage Disclaimers
Be warned, when you give Cortana access to your email and other services, you are opening your personal data to the assistant, and therefore, to Microsoft as well. You should definitely review the disclaimer that appears before connecting these accounts, as it will explain how your data is going to be used. If you have second thoughts after reading this disclaimer, you can be directed to where these integrations can be deactivated.
Since there isn’t any indication, as of yet, as to which of Cortana’s commands will work with these Google services, we are given the opportunity to speculate freely. What functions do you think Cortana will have in regard to Google’s apps? Give us your ideal list in the comments!