One thing I (and many non-technical friends) found creepy recently is how Google Maps monitors your phone camera. An update quietly pushed this on-by-default feature for the purpose of prompting you to add images to their product.

I wrote more on this and how to disable it here: https://unop.uk/on-google-maps-geotagging-and-privacy

Edit: looks like they have pushed out at least two new on-by-default features since I wrote this (not that long ago); 'photo view count opportunities' and 'new and popular places'.