Adrianne Jeffries, an investigative reporter for The Markup, discovered something eerie in her Kindle data on Tuesday. Amazon meticulously tracks every single tap, essentially keylogging whenever the screen is pressed. Jeffries received approximately 90,000 rows of keylogging data in a file titled Devices.Kindle.Reading.Actions.

Should you be worried? — A response on Twitter from her podcast co-host John Lagomarsino posits that this kind of tracking is usually necessary to inform the reader of their reading speed and provide accurate estimates.

This data also includes (cropped out) book titles, so this provides Amazon with useful advertising metrics. The advertising angle could explain why this data is stored for so long instead of just calculating your reading speed on the device itself. Less ominously, the book titles help track tapping to the next page for Kindle Unlimited, which pays authors per page read.

If this seriously freaks you out, there’s a dedicated community of Kindle hackers out there trying to keep Amazon out of their reading habits.

You'll need an older Kindle to take advantage of these tips and tricks, but they mostly try to find ways to keep the devices from connecting to the internet (and thus the Amazon machine). You can access your Kindle data here (it will take some time if you're an avid reader). Then you can decide whether you want to become a hacker or just go back to physical books.