With the Incredimail inbox, you get more info about messages with the limited number of messages on the page. You also can touch a message pane and swipe up to see a preview or swipe down to access controls for deleting, forwarding, and other actions.
Updated:Caption:Jason ParkerPhoto:Screenshot by Jason Parker/CNET
An added bonus is the Facebook photo inbox that shows you the latest photos to be submitted to your Facebook feed. You can only "like" a photo (no comments), but the problem is that the app requires that you let it post on your behalf to your Facebook timeline.