Want to add your Google (or other) Calendar to the iPad's Calendar app? No problem. In Settings open Mail, Contacts, Calendars. Add an account and tap on Other. Tap on Add CalDAV Account and enter your Google Account credentials (the Server is www.google.com). Exit the Settings app and tap on the Calendar app and all your events should appear. By default all calendars are displayed, but you can tap on the Calendars button to choose which ones are shown.