Android makes it very easy to add nearly any Google service to the platform, but when it comes to adding various other third-party services, such as an iCloud calendar, there really isn't an easy way of doing it.
If you're already entrenched in iCloud and sharing calendars with family members and colleagues who are using iOS and/or OS X, switching to Google Calendar may not be the easiest thing to do, for all involved. I'm not saying it isn't possible, but it won't be seamless for those who aren't switching devices. Thankfully, there's an app that can help make the transition a bit smoother.
SmoothSync for Cloud Calendar is an Android app that can, and will, save iOS users making the switch to Android from the agony of switching where their calendar is stored.
With SmoothSync for Cloud Calendar, you simply log in to your iCloud account, select the calendars you want to sync with your device, and let it do the rest. It's really that simple. You'll even get to keep the calendar colors you assigned your various iCloud calendars on your Mac or iOS device.
I did run into some issues with my initial sync, but the developer was easily reached via e-mail and everything was resolved. (Turns out the issue had nothing to do with the app.)
You can download SmoothSync for Cloud Calendar from Google Play for $2.67.