'They know us better than we know ourselves': how Amazon tracked my last two years of reading

Amazon knows more than just what books I've read and when - it knows which parts of them I liked the most

When I requested my personal information from Amazon this month under California's new privacy law, I received mostly what I expected: my order history, shipping information and customer support chat logs.

But tucked into the dozens of files were also two Excel spreadsheets, more than 20,000 lines each, with titles, time stamps and actions detailing my reading habits on the Kindle app on my iPhone.