For instance, in Android, Google tracks with GPS accuracy your whereabouts constantly. This isn't just what IP your desktop is attached to. Furthermore, there is no prompt telling you this happens with a very easy way of undoing. In fact even if you knew about this it is very hard to find a way to disable.
Secondly, Chrome send every website you visit to their servers to be logged. Again, this is not explained in some easy opt-out screen and in fact the only way to get around this is to use SRWare Iron, where they removed that code.
But Microsoft makes it easy for you to choose the privacy options even telling you about them on install.