I'm looking for an app where I can scan the barcodes of my classroom library books to keep track of what I have. I don't need to be able to check books in and out for students, so this feature isn't a necessity. It would be nice to be able to look books up by title and/or author. I did a search, and most of the apps that I have come across require you to enter books manually, or they are paid sites (like Book Retriever). Any suggestions?