On my iPad I have these apps:
State Parks
Oh, Ranger
Allstays
Mobile RVing
Campwhere
My favorite is allstays.
Kind of related, the Rand McNally atlas is also on there. This E version is exactly the same content as looking at the big paper atlas. Love it. You can zoom in on a small part of the state, etc.
Another app I really like and use a lot is weather underground ( wunderground dot com ). With this app, when you select hybrid view, you get a map overlay of the full hi-res satellite image. Where it can, you can get all the way down to birds-eye view. I have found it useful to look at a sat pic or birds-eye prior to driving someplace that may be in a congested area, because it gives me a visual of where I am going.
Sorry....kinda got off on a tangent there......:)