You can scroll around the map and zoom in on readings. Readings are continuously updated every few minutes. It displays the current ionizing radiation reading from these detectors on an easy to use world map, in uR/hr, one of the standard units of measurement for radiation. You can scroll around and zoom in to your area. Typical background (naturally occurring) radiation values near sea level are in the 10 to 20 uR/hr range. Higher readings naturally occur at higher elevations due to cosmic rays from outer space. Tapping on one of the readings will bring up a chart of the last few days worth of readings. You can even smooth out the variations by adjusting the number of samples averaged per plotted point, to bring out subtle variations. Buy a copy of Radiation Map Tracker, and you'll never be in the dark about nuclear radiation levels again.