Hi

No, that’s just the way GPS is working – GPS is good at lat/longitude positioning, but not very accurate for vertical positioning (and subject to a *lot* of drift, say, up to 100m).

On top of that, GPS altitude follows the WGS84 ellipsoid, which gives a ‘mean’ sea level (and not your actual sea level) as this is basically subject to how dense the planet is in various locations (affecting the natural shape of the planet), so you can think of earth as a not very symmetrical ellipsoid, which is where another discrepancy vs sea level will come into play.

It’s measured in meters or feet(ft) (depending on your unit selection in the settings) and isn’t affected by the unit conversion for other units (I have just double-checked)

I know this is an old thread, but it seems most relevant to a problem I’m seeing as well: Torque reports a GPS altitude that is significantly different than other apps running on the same device. I recall from working on this several years ago that there is a correction factor that must be applied to the raw data. The WGS84 data is based on a elliptical earth, but we usually give altitude relative to sea level. A correction must be applied. Here is a link to an explanation:

http://stackoverflow.com/questions/11168306/is-androids-gps-altitude-incorrect-due-to-not-including-geoid-height

A quote from that page explains the correction needed:

“The altitude you get from GPS is the height above the WGS84 ellipsoid in metres, which is an approximation of the earth’s surface. I know that because I’ve been developing Android software to use it.

A correction has to be applied to convert the figure to height above mean sea level, or altitude as it is usually known.”

Hope this helps…
Will