If you have a certain mountain you'd like to know the name, you can use the function of the direction sensor. Check for north first, then lay a map alongside in the same direction. Next, measure the direction of the mountain you'd like to find, and where it is located on the map from the point of North.
Then, placing it on the map, center yourself to line up with the angle you measured from the north. The mountain is on that line.

PROTREK's Bearing sensor lets you locate yourself on an area map by plotting lines from two fixed distant landmarks. Begin by orienting the map with the Bearing Sensor. Next, select two mountains or other landmarks you see in the distance. Now use the Bearing Sensor to measure the angle of these points with respect to magnetic north* and draw lines on the map along these angles. The point at which the lines intersect will be your approximate current position.
*Note that magnetic north, detected by the Bearing Sensor and other magnetic compass, differs from true north.