Fitness trackers with altimeter

Altimeter

— the feature of measuring the height of the terrain. Theoretically, it can provide the measurement of height above sea level; however, in fact, the altimeter more often works in the format of determining the difference in height between the start and end points (for example, the sidewalk and the roof of a building). Note that this feature does not necessarily mean the presence of a barometer (see the related paragraph), although the altimeter usually uses an atmospheric pressure sensor as well.