As a former Kindle developer, I can say that most of what's mentioned in this article are metrics used to understand how the features are used (bookmarks, highlights, dictionnary, etc.), how much they are used, and in which country. This allows the teams to focus on features that are actively used, and sometimes lead to discontinuing features that see little to no use. Hope that helps.
Back when they had a cell phone in them. I was standing behind a guy who was supporting it. "Uh lets bring up where you are at? It says you are 10 miles off the coast of miami?...." "oh yeah I am calling from my yacht" "do you see any cell towers?" "no" "It kinda needs those to work. I am surprised I got the location data."