Originally Posted by ApK
I convert the epub to mobi and put it on my Kindle. Eventually, I see page number info, so I apparently got an .apnx file from Amazon? Did the Kindle phone home with the title and author of every file on my Kindle, and Amazon was nice enough to respond with an .apnx file for any matches in it's database?
No. If you used Calibre to convert to mobi, then Calibre put the .apnx file on your Kindle. Not Amazon. The Kindle Interface Driver plugin in Calibre now sends the .apnx file file by default.
But they're "calculated" page numbers. They don't coincide with a specific physical incarnation of the book.