Google cross-correlates everything that passes through it. Your search terms and what you click through, your youtube history, comments, and patterns, gmail text, recipients, senders, topics, and dates, fitbit users/data/locations, waze location, all their cloud services and their use, anything where you authenticate using google, not to mention any ‘sharing’ agreements with other companies and governments.
On book they earn mostly from advertising revenue, secondly cloud, thirdly subscriptions and devices. https://www.statista.com/statistics/1093781/distribution-of-googles-revenues-by-segment/
Thanks for the reminder. I just got a Fitbit Inspire 3 watch. All black, not some girl colors, which most Inspire 3 bands are — No wonder they are also called fitness trackers. F’ing google tracks you with it. I must check my Fitbits location settings. I think I opted out on that.
So now you can be tracked via your phone. And via your fitbit which is most useful when you wear it all the time. Even when sleeping. It is a sleep monitor too. How long you slept. Your O2 levels when sleeping and more.
Warning — This model fitbit will not give you on the fly O2 readings. Only records your O2 while sleeping, that you can read the next day. This must be great if you have sleep apnea and similar.