Music library apps and calibre manage a "library" because many of the features center on metadata.
A music management app can navigate a large quantity of files via more effectively than clicking through artist -> album -> track hierarchies. You can ask it to find music by a particular genre, time frame, rating, tag, etc etc.
You can ask it to show things you commonly listen to or things you haven't listened to or haven't listened to recently.
Beyond this it can offer you the ability to perform a variety of operations on your selection whether its the antiquated notion of burning it to a disk, streaming it over the network, converting it to a different format finding more music by the artist etc.
Similarly calibre offers a way to dig through a substantial collection of ebooks in a lot of different way and perform operations on same.
Example. Find all the ebooks that don't have an epub or pdf format available and convert whatever existing format they do have to epub.
Find all the books that match a particular query that aren't on the currently connected device example foo bar baz and ondevice:false
Then send wirelessly to device.
Given a bunch of books for which some pieces of metadata is lacking guess what metadata probably matches and let me review your guesses.
A music management app can navigate a large quantity of files via more effectively than clicking through artist -> album -> track hierarchies. You can ask it to find music by a particular genre, time frame, rating, tag, etc etc.
You can ask it to show things you commonly listen to or things you haven't listened to or haven't listened to recently.
Beyond this it can offer you the ability to perform a variety of operations on your selection whether its the antiquated notion of burning it to a disk, streaming it over the network, converting it to a different format finding more music by the artist etc.
Similarly calibre offers a way to dig through a substantial collection of ebooks in a lot of different way and perform operations on same.
Example. Find all the ebooks that don't have an epub or pdf format available and convert whatever existing format they do have to epub.
Find all the books that match a particular query that aren't on the currently connected device example foo bar baz and ondevice:false
Then send wirelessly to device.
Given a bunch of books for which some pieces of metadata is lacking guess what metadata probably matches and let me review your guesses.