The Color Pinwheel of Death

I got this app in order to view USGS topographic maps downloaded from the USGS Store. Nat Geo’s Topo is no longer available, and I have to find an alternative for my MacBook. When I try to view a quad I get the color pinwheel. When I try to move around a quad I get the color pinwheel. When I agree to rate the app I get the color pinwheel. I sure hope there is a better app somewhere.

Albuquerque born about PDF Reader++