EGM96 High Precision Geoid Undulation
To a more actual geoid model: https://play
EGM96 High Precision Geoid Undulation
To a more actual geoid model: https://play.google.com/store/apps/details?id=tools.gnss.highprecisiongeoidThe principal aim of this app is calculate, being offline, a high precision geoid height undulation (N) to be used in field by engineers, topographers and cartographers who are using a GNSS receiver with high precision coordinates too. The GPS from your phone doesn't give to you a high precision ellipsoidal height so it isn't a good idea use it to obtain the ellipsoidal height (h). Undulation of the geoid (N) is the mathematical process of determining the height in meters , positive if above or negative if below, relative from the geoid to a ellipsoid provided by the GNSS system. The height given by you GNSS receiver it's referred to a specific GNSS ellipsoid like WGS84 and is called ellipsoidal height (h).The best approximation for your topographic height it's called orthometric height(H) obtained by the formula: H = h - N.This app calculate Geoid Undulation using EGM96 15' x 15' grid http://earth-info.nga.mil/GandG/wgs84/gravitymod/egm96/intpt.html interpolating it with CSPLINES Piecewise Bi-interpolator from Apache Commons Math 3.6.This can be used as free version of more precision EGM2008 2.5'x2.5' grid found at https://play.google.com/store/apps/details?id=tools.gnss.highprecisiongeoidIt's works offline so you don't need be connected to use it.It's only needed be connected to download it from play store.