Peter,
Thanks for your honest feedback. iFly GPS was first designed to be a Navigation solution for the air. We have been closing the gap and improving the flight planning, supplemental information and have many more improvements to come. Expanded Weather features and Preflight Planning are definitely on the short list.
Now as for Topo, we feel there is some opportunity here for mountain flyers and even VFR pilots in Canada and Alaska. Topo charts would be extremely handy for them. It's on our wishlist, and we are just monitoring demand at this time.
Glad you like iFly GPS better I the air, that is where it really matters, but know that we are continually improving the planning and weather side.