I use Google for just about all of my online data collection (calendar, mail, contacts, etc.), and I find it a great service, especially for free. The fact that all my devices can see and use that data is just icing on the cake. Something to think about is that the iPad doesn’t see all the google calendars that you subscribe to by default, and getting to them isn’t intuitive at all. Good thing someone has done this already, and I’ll attempt to break it down.
Open Safari, and navigate to m.google.com.
Tap the sync icon/button, and tap “Sign in with your Google Account”.
Enter your google information, sign in, and tap, under Manage Devices, your iPad.
Check the Shared Calendar that you need access to, and tap save.
True, it’s not very intuitive, but it’s there. I hope this helps.