Playa 2.1 introduces two new “UI modes” – alternative interfaces for your Publish pages. Each are available to both normal fields and Matrix cells.
This is the classic Playa interface. It is composed of two panes. On the left is a list of each of your available entries, and on the right is a list of your selections. To select an entry, simply drag it from the left pane to the right, dropping it in your desired sorting position.
There are two drop pane UI Modes: “Drop panes with filters” and “Drop panes”. They are identical except that the former also includes a filter bar on top of the left pane, which lets you filter it by Keywords, Channel, Category, Author, and Status. These filters only affect what you see in the left pane, making it easier to locate entries, should you be dealing with a large number of options.
If you have no use for custom sorting in the Publish page, a simple multi-select input might be adequate.
If you only want authors to be able to select a single related entry (like EE’s built-in Relationship fieldtype), choose the Select UI Mode.
Regardless of which UI Mode you choose, you can still take advantage of all of Playa’s other features – multiple channel selection, searchability, and the full range of template tags and params.