We are modeling our application as a finite state machine where states are tied with corresponding views. The main form will be responsible for orchestrating the views in front of the user and will make use of TFrameStand to manage this task.
Views are built using TFrame descendants, one for each view (in more complex scenarios, you may want to have hierarchies of TFrame descendants or compose them as needed).
As a general note, you can create a new frame in the IDE by selecting the File | New | Other | Individual files | FireMonkey frame.
The following screenshot shows the IDE New Items dialog with the FireMonkey Frame entry selected:
I tend to follow this naming convention for frames/forms, such that each frame has its own unit with a uniform name, that is, TFooFrame | Frames.Foo.pas. Remember...