Part 1: Calendar
I've done the hard work for you - just install Sunrise Calendar from the Play Store then configure it for iCloud. Easy!
Slightly longer explanation:
Install Sunrise Calendar and launch it.
Connect with Google.
Add your iCloud account.
Told you, Easy!
Now you can add stuff on your Android phone and it will push to your Mac desktop iCal app, and vice versa.
And this is all thanks to the new good guy Microsoft (can't believe I just typed that but there you go - once bitten twice shy and all that).
*EDIT: after disconnecting from Google, Sunrise gave me an authentication error. So you need to Sunrise to remain authenticated with either Google or Facebook (second time around I chose Facebook since it has event calendars I actually refer to occasionally).