calibre

This software forces you to copy your entire ebook collection into a single directory. The developers aren't willing to consider anything else. Additionally, it doesn't modify the original files. So literally, this software will — without confirming with the user — duplicate your entire reading collection.

I've used the application for a number of years now and am abandoning it for good now. Can't believe this software won't let you manage a collection manually. I don't know about other users, but my reading collection contains both fiction and educational material, which I've spent a great deal of time organizing to be accessible. I'd love to use this application but it's just not possible unless you want to mix EVERYTHING you have into one folder. Yet another application that could be 100x better with little to no change but wont because the developers are religiously bound to a flawed approach to ebook management.

I recommend using another application called Blio for personal reading needs. It also has a flawed approach to file management, but it makes up for the fact with looks.

Calibre is primarily a powerful ebook organizer and secondarily a viewer. For smaller epub and mobi files I find that Calibre works well enough even if the internal reader is simple. I suggest users setup Calibre to view PDF files in either Okular (linux) or SumatraPDF. The internal reader tends to be slow or occasionally crash with larger or unusual files regardless of ebook format.

You should take note of where Calibre is storing it's ebooks (Calibre Library icon > first line of text will contain your folder/path). From here add this path to a backup program so that you don't lose all the work you will eventually put into Calibre.

Calibre is incredibly good software and updated often. I have donated to the project twice and recommend others do so as well. $5 (or less) goes a long way towards helping the creators of open source software.

Where are you getting ebooks that don't have ISBNs? Commercial ebooks do have ISBNs and Calibre does have the ability to extract those (or download from multiple online metadata sources) and list them in a column.

Calibre does copy all ebooks into a single directory PER LIBRARY. I have yet to determine the limit on how many libraries it will support, but I currently have separate library folders for Fanfiction, Short Unread Fanfiction, Long Unread Fanfiction, Unread In-Progress Fanfiction, Commercially Published Fiction, Cookbooks/Gardening, Manga/Graphic Novels, Nonfiction, Poetry, and a fileless database of my Physical Fiction collection (which I brought in as a list of ISBNs I scanned with a barcode reader into a file on my computer).

More than about 2000 books in a library does tend to slow it down, which is why I subdivided my libraries. A library with only metadata and no book files opens very fast.

Calibre does have an update notifier. When there's an update available, there will be a link at the bottom right. It does require you to download and install the update, but that's not really all that hard.

Calibre is primarily aimed at managing books, so all entries in the library are called "books" but the program will handle image, video, and audio files as well, and call your default program for that filetype when you click on it to open. Each "book" will accept multiple files, as long as there is only one of each format. For example, one book can have PDF, EPUB, MOBI, MP3, MP4, PNG, JPG, and ZIP, but you can't have a folder full of JPGs. Honestly, that's my main gripe. I prefer my graphic novels and downloaded webcomics as individually numbered image files, rather than forcing them into EPUB or ZIP.

There are lots of useful plugins, and if the default metadata options are insufficient, Custom Columns can be created. Too many Custom Columns may impact performance, depending on how many books Calibre has to sort when you use them, but you'd have to go pretty crazy with the columns.

There don't seem to be any AV-related metadata plugins yet. Someone requested an IMDB metadata plugin years ago, but since plugins are made by volunteers, there apparently hasn't been enough interest to get it done yet. Maybe someone could be persuaded to customize the Ant metadata scripts for Calibre...

When I moved away from proprietary ebook readers, Calibre saved me when it came to transferring my ebook library to epub format. It's simple, quick, and being able to edit the metadata to change sort functionality is an added bonus.

While its library management is flawed (yes it is), it is unparalleled when it comes to viewing (with the ebook-viewer app) and conversion (with the ebook-convert command line utility), which can be used without adding the book to the calibre library.

I use it exclusively for converting epub to mobi for viewing on a kindle without jailbreak.