Yes, you can. Calendar Op.2 shares your calendar data with the standard iOS Calendar app, so you can setup syncing with Google Calendar using standard iOS Calendar syncing feature by following the steps below.
- Launch ‘Settings’ app from the home screen.
- Go to ‘Settings’ > ‘Calendar’ > ‘Accounts’.
- Select ‘Add Account’ > ‘Google’.
- Sign-in to your Google Account.
Please also refer to the Google Help Page for more details.