Every point where the field was measured, shown where it sits on the accessory. Choose a setting when the test has more than one, then click or tap a layer in the stack to the left of the picture (above it on a phone). Hover over a point, or slide a finger across the points, to see its position and the field strength measured there. Every layer is colored on one scale, so a layer farther from the surface reads cooler. Pinch, or hold Ctrl and scroll, to zoom in.
Loading the measured points.