Not everyone uses Google's Calendar product, and if it is used, often the "main" calendar is not really the user's main calendar. Up until now Google Now would only work with the main Google Calendar connected to a Gmail account to display cards for upcoming appointments.
Recently, Android Police went through every line of code in the latest Google Search (Google Now is part of Google Search) update, revealing new features in Google Now, along with probable upcoming features. One of the new features that's largely gone unnoticed is the ability to pick and choose which calendars Google Now will use when showing appointment cards, no matter what service the calendar originates from.
For example, I use SmoothSync for Cloud Calendar to sync a couple of iCloud calendars to my Android device, and after the latest update of Google Now, I am now shown appointment cards from my iCloud account.
- To manage which calendars Google Now can use, simply launch the app and scroll to the bottom of your cards. From there, tap on the menu button and select "Settings" followed by "Google Now."
- Halfway down the list of available Google Now services you'll need to find and select the Next Appointment entry.
- From here you can see a list of the calendars on your device Google Now will use to display appointment cards. Removing a calendar from the list is as simple as tapping on the check box and removing the check mark.
Should you change your mind later on and want to add the calendar back to Google Now, revisit this same settings page and tap on the box.