That's the easiest to avoid. Ghostery, or a simple edit to your /etc/hosts file.
The problem is that tracking is much more pervasive, and there are many more ways you can be tracked that are much harder to block than Google Analytics.
What about for iOS? Sure there's more pervasive methods, but I doubt any are as ubiquitous as GA. My ghostery plugin shows GA for nearly every website I visit.
There are adblockers for iOS, but not for old versions of iOS and I think 32 bit versions of iOS don't work with it. IIRC Apple has allowed it since 9.0.
Try Privacy Badger, made by the Electronic Frontier Foundation. It protects you from many trackers, not only Google's, for example it disables the tracking capabilities of Facebook like buttons. https://www.eff.org/privacybadger