Flitedeck is a moving map product, basically, which picks up a routepack prepared in Flitestar or Jeppview. It also contains some route editing features.
I found FD clunky and buggy and stopped using it early on.
I use Flitestar IFR, pasting a route into it from Flight Plan Pro. The basic workflow is described
here but there are multiple ways of doing this kind of thing; FPP alone is good enough by itself if you don't need a pretty enroute chart.