I use PBS to organize my TBR pile of paper books.

I have a nook that I have used the N2A card and now it is an android tablet. 

How do you all keep track on what's on your kindles and nooks?  Is there an app you use?

No app, but I create a bunch of shelves on my Nook to keep them organized. Reading, TBR, Challenge books, Not sure about, Unshelved.

I dont use any apps for this either. I do, however, have 5 pages of 'categories' on my kindle. When i download new books to it, i immediately put them in their correct categories. This works perfect for me.

I make Collections on my K3   Collection names are 1st Author --- Series  [ Example Rita Mae Brown --- Mrs Murphy....   or Rita Mae Brown --- Fox Hunting..... or Rita Mae Brown ---  Non Series]    I now have 9 pages of collection But would have 65 pages to look thru IF I didnt make the collections LOL  That just about 600+ in books LOL 

On the Literati you cant make collections UGH 

I have the Nook + n2a card also. However the only books I have on it are kids books in the Kindle app. I read my books on the Kindle, and I have 1 page of categories, including 1st in series, series read next, paranormal non-series, other, apps, reference, and MM.

I also sort my Kindle by subject/category. That works one for me. 

Although, I might add a new category. I've been downloading a lot of free eBooks, and not all of them are "must reads." I figure I can just delete them as I read them. However, there are a few that have really exciting descriptions and I want to check those out first. But, once they get added to my Kindle, I can't remember which ones they are, especially if it's been several days and I've added more books. I might add on an extra category to highlight those books: "Of Special Interest," and make sure they go in that category as soon as they get added to my Kindle.

For Freebies I never read or authors I never read LOL  I have a Collection called  Amazon Freebies & Cheepies! right now I have 150+  After I have read them & I dont think I going to re-read again I delete!   IF its interesting I move to Keepers???  right now about 20 in this! IF I get say 3 of a author I beginning to like I make a new Collection & move them to that!   Helps to keep things organized! 

Most freebies never make it to my Kindle. I either send it to the Cloud or to k4pc, or to k4android (kids books, to the Nook Color) or to my first kindle (kids chapter books). Sometimes I will send a really short smutty book to my kindle, so I can read and delete. I delete those from the archives, too.

Some of those indie books have atrocious formatting so I like to put them in Calibre and look at them, reformat if needed, then send to the Kindle from there, when I am ready to read them. I refuse to read a book that isn't formatted like a book.

I don't keep any keepers on the Kindle. If I want to reread I will resend to the kindle.

I use Book Crawler on my iPad.  I note the format as eBook, and then make a note of the file type (Kindle, Nook, Adobe, etc.) so I know which reader and/or app to use for each book.

I use Calibre and keep all the files on my main computer. I have a tablet with apps for Kindle, Nook, plus a couple other readers so I move the files to the tablet in batches that I want to read. I have about 150 books.

i have NOOK and Kindle for PC both installed on my PC and keep all the books i have for each one listed into different categories .. some by genre and others based on author/series.

I have a NOOK. I created a shelf for my favorite genres, and a TBR pile. My TBR shelf is on top so when I am ready to start a new book I can go straight to my shelves, and my unread books pop up first. My unread books are only allowed on my TBR shelf, when I have read the book, I take it out of TBR and onto the proper genre shelf.

i use librarything.com  (200 books on your shelf for free, then $25 for lifetime membership.

Others use goodreads or shelfari.... & I am sure there are a few others.

Some also use a spreadsheet, like excel.

I have my Sony EReader organized by topic by using the "library" function, mostly.  I have the Oz books all in one "library", though.  Unless it's also in hardcopy, I don't normally actually keep track of what I read on my EReader. 

I HIGHLY second the Calibre recommendation. I have around 1000 books and it manages them flawlessly.  It is free, pretty easy to use [if you're used to either itunes, or some other media library program] and is constantly being updated and improved by the developer.

For more specific info, check out:

http://www.mobileread.com/forums/forumdisplay.php?f=166

Another Calibre user who would highly recomend it.  Hundreds of books and works like a charm.  My only gripe - I would like to access my databse (list) of books and metadata on the iPad - because Apple's iBooks does such a poor job with orgainizing and shows only author, category and title. 

I guess my real gripe is iBooks - Calibre is fantastic for large book collections.

(yes I know there are other readers out there, but I very much like the reading experience in iBooks - like the page turn animation makes me feel like I'm really reading a book, it looks fantastic and it always shows me how many pages left in book AND left in chapter) I just think it about the worst reader for LISTING and catagorizing books.

Calibre also has a number of apps to enhance the already fine program.

-RD