By Brian R. Fox
U.S. Geological Survey (USGS) The National Map Topographic Maps and Data are now available on mobile devices that use Android and iOS operating systems. Android and iPhone users can now use their mobile devices as digital topo maps, leveraging the power of the Global Positioning System (GPS) to zoom in on their precise location while hiking, biking, running, or engaging in any other activity that benefits from precision navigation. The type of data that are available includes USGS imagery and topographic maps from The National Map, as well as road and contour layers.
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