Your website (desktop) version of your Calendar account has numerous settings. The settings include general settings, security settings, notifications, connected calendars, billing, and referrals.
However, we have limited these settings in the beta version of our mobile app. You can see your timezone as well as your default and connected calendars.
All of the other settings are still available. You'll just need to click on the website listed in settings to access them through your website version of your Calendar account.