You can easily hide the details of private events on integrated calendars.
FROM THE WEB APP
Step 1: Go to Settings > Calendar Integration
Step 2: Select the calendar you want to make "Private"
Step 3: Select your privacy setting.
Step 4: Done.
Private events will display on your Gazelle calendar as "Busy"
A good use case for this is when you are sub-contracting (or working for a company) and you want to keep some of your private customer details hidden.