A List, as the name suggests, is a list of items. In the app there are two kinds of lists: global and private lists.

Global lists

A global list is accessible from all the collections, go to Settings → Lists to manage global lists.

Private lists

A private list is accessible only from the collection in which it was created.

To manage private lists, open a collection and tap on the button (top-right corner), then select Lists.

To select list items in a document, add a Selection field to the collection.