PanelKit

This framework does all the heavy lifting for dragging panels, pinning them and even moving/resizing them when a keyboard is shown/dismissed. A lot of effort has gone into making the API simple for a basic implementation, yet very customizable if needed. Since PanelKit is protocol based, you don't need to subclass anything in order to use it. A panel is explicitly (without your action) shown in a UINavigationController, but the top bar can be hidden or styled as with any UINavigationController.