A Keeper!
I use around 6 map apps on my iPhone at any one time and have tried several others. My main use is route finding by car in remote Western areas with only cached maps. I use for hiking, too, but dont do route finding with waypoints.
This app downloads data fast, lets you compare different maps all in one view, and permits saving Google satellite images. It often takes 2 or 3 map types to analyze a location, say for car camping, in advance.
I also recommend the various GIS map apps, called Geog[State] or Geographic[State], meaning for each state. They have land ownership, geology, roads, landmarks, fire hazard level, etc. The only data I cant find and save is detailed vegetation.
Prof Tweed about
Offline Topo Maps, v4.0.1