Updated: see below.
I recently upgraded to Android 5.1 on my Nexus 10. One app I often use is Google Maps. This has a "show my location" button:
When I clicked on this I got the following dialog box:
Notice that I have two options: I either agree to let Google track me, or I cancel the request. There is no "just show my location" option.
As a matter of principle, I don't want Google to be tracking me. I'm aware that Google can offer me all sorts of useful services if I just let it know every little detail of my life, but I prefer to do without them. But now it seems that zooming in on my GPS-derived location has been added to the list of features I can't have. There is no technical reason for this; it didn't used to be the case. But Google has decided that as the price for looking at the map of where I am, I now have to tell them where I am all the time.
I'm aware that of course my cellphone company knows roughly where I am and who I talk to, and my ISP knows which websites I visit and can see my email (although unlike GMail I don't think they derive any information about me from the contents), and of course Google knows what I search for. But I can at least keep that information compartmentalised in different companies. I suspect that the power of personal data increases non-linearly with the volume and scope, so having one company know where I am and another company read my email means less loss of privacy than putting both location and email in the same pot.
Hey, Google, stop being evil!
Update: 20th April 2015
A few days ago a new update to the Google Maps app got pushed, and its now no longer demanding I let Google track me. In fact the offending dialogue box has now been replaced by one with a "No, and stop pestering me" option, so this is an improvement on what they had before.
Way to go, Google!