[GrandmaVS]

I haven't changed cards from one reader to another when in the middle of a book to see if it keeps track. I am usually reading a different book on each reader. I will check it out to see if it keeps track on the card and if the bookmarks are shared.

Update:
The bookmarks and place in the book didn't hold when switching the card from one reader to another. I keep a duplicate copy on my cards so that I can switch back and forth without removing the cards. I find on the 7" color reader that it is easier to copy the book I am reading to the main memory of the reader so I don't have to search through the list on my card. My Libre pro keeps track of several "recent" readings, but the 7" color only shows the last opened book.