Google Calendar has been available in iOS since 2015. However, now this has gone ahead and is optimized for iPad as well.
Image Source: itunes.apple.com
The app is pretty similar to the version that is already available on the App Store. Now, you will be able to use Spotlight Search in order to find items from the home screen of your iPad. Also, you will be able to switch your Views between days, weeks, and months. Not only this, the new app gives you ability to create new events with the suggested places and titles that Google provides based on the preferences and availability of other people.
You can now easily go on to update Google Calendar app from here.