what do you call the instrument that indicate north
A smartphone that can be used as a compass because of the magnetometer inside. A compass is an instrument used for navigation and orientation that shows direction relative to the geographic cardinal directions, or points. Usually, a diagram called a compass rose, shows the directions north, south, east, and west on the compass face as abbreviated initials. When the compass is used, the rose can be aligned with the corresponding geographic directions, so, for example, the N mark on the rose really points to the north.