It's bound to, as it's a phone OS created by Google and designed to keep in contact with Google (to a degree dependent on how much you agree to in the settings). I'd imagine an Apple phone conversely sends more data to Apple than an Android phone!
But it does communicate more in general too, so it can give you a somewhat more useful "suggestion / PA / automation" kind of system powered by Google's cloud than iOS/Siri powered internally on the phone, at some expense of privacy of course. If you agree then it GPS tracks you when it detects physical activity so you can look at your route later, for example, wihtout having to remember to ask for it at the start.
It's not necessarily some evil plot to abuse people - they throw things in your face all the time (to the point it gets quite annoying on the Google website) reminding you of your data choices and explaining the privacy implications so that you can make an informed decision as to what you're comfortable sharing.
Though seemingly the press wants everyone to remain brainless and have things decided for them, which makes a "just hammer yes to everything and don't read anything" approach to setting up an Android handset pretty uncomfortable from a privacy perspective.
