LibraryThing is a service app that allows personal online book cataloging and access from any Internet browser, including those on mobile phones. The LibraryThing app has several features including a combined book catalog database that lets people with the same books connect. It can also make reading suggestions.

Free accounts allow catalogs of up to 200 books, paid are limitless. Privacy features allow users to participate incognito.

Borrowing and swapping books is eco-goodness and the app includes an area for borrowing or swapping books—which saves on trees.