[sneak]

Apple Books sends what you're reading, and how often, and when (and approximately where, via client geoip) along with your unchangeable device hardware serial number to Apple.

Remember when librarians basically revolted because the patriot act let the feds get library borrowing records without a warrant? Apple's Books app is several times worse. It's nonconsensual spyware, even if you use only your own local files and never engage in trade with Apple for ebooks.

Don't use it.