[Tagging] RFC ele:regional

[Greg Troxel]

Peter Elderson <pelderson at gmail.com> writes:

> Thanks for explaining why my android phone says I am at +38m (+/- 3) in my
> backyard when in fact it is at Dutch sea level -4.4m.

Well, I didn't quite.   The location API returns HAE.    For a program
to show that value to a human as "elevation" is buggy.   So in addition
to what I said, you have to add "your software is buggy".   File a bug
with that app!

On Android:

  install GPSTest (available in F-Droid).  It will show two heights.
  One is mislabeled "Alt", when it should say HAE*, and the other is "Alt
  (MSL)" which is the WGS84 sea level type height.
  * I have discussed with the author, but the notion is that people will
    be baffled by HAE.  However, I think that's better than
    misinterpreting it as a gravity-based height

  install OsmAnd.  In addition to maps, get the "World Altitude
  Correction" map.  This is really the WGS84 gravity model, and when it
  is loaded OsmAnd will convert HAE from Android to height above the
  WGS84 gravity surface