altitude

I am trying to get Altitude of my location in my application. But every time I try altitude property of CLLocation object I am getting 0.00 as result. I googled for my query and I got a similar question here and here . This link is saying that if I access CLLocation with wifi or cell tower it will be null. Even if I try to set desireAccuracy to best than even it don't make sure that app will use GPS. It is also saying that if I am indoor that I won't be able to access GPS. I many cases it its not sure that app will use GPS only. I want some way for getting Altitude from wifi or cell tower too.

Prior to iOS 4.0, CoreLocation was reporting altitude correctly, now it always reports as 0 ft. -(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation*)newLocation fromLocation:(CLLocation *)oldLocation { NSString *tLatitude = [NSString stringWithFormat:@"%3.5f", newLocation.coordinate.latitude]; NSString *tLongitude = [NSString stringWithFormat:@"%3.5f", newLocation.coordinate.longitude]; /* the following returns 0 */ NSString *tAltitude = [NSString stringWithFormat:@"%i", newLocation.altitude]; /* theres more code, but it's not relevant, and this worked prior to

I tried to find how to get the altitude above the mean sea level. At this time, it returns altitude from the ellipsoid. So, anyone knows the formula or calculation to change the altitude value from ellipsoid to the altitude value from mean sea level. Thank you for all help As you mentioned, GPS returns the altitude as an offset from the WGS84 reference ellipsoid, but most people want to see mean sea level (MSL), and the two frequently don't agree. The way this is most frequently done is by looking up the delta in a table and using that to compute MSL based on the height from GPS and the delta

Is there a way to obtain altitude aside from Location.getAltitude()? I've heard using Sensor but don't have idea and can't find on net. UPDATES1 I found SensorManager.getAltitude(float, float) using API Level 9 up but don't have idea on how to implement it. Would you share with us. I know it's late but for anyone looking for it, that might help import android.app.Activity; import android.hardware.Sensor; import android.hardware.SensorEvent; import android.hardware.SensorEventListener; import android.hardware.SensorManager; import android.os.Bundle; public class MyActivity extends Activity

I need to get an accurate measurement of altitude using GPS only. I tried Location.getAltitude() , but that is terribly inaccurate. Any advice? There are two issues with using altitude of a smartphone / tablet GPS: The altitude is the altitude above the WGS84 reference ellipsoid. It is not the altitude above ground level or sea level. Here is more detail on that: http://www.gpspassion.com/forumsen/topic.asp?TOPIC_ID=10915 . This error can be corrected; here is a description how to do that by hand: http://www.unavco.org/edu_outreach/tutorial/geoidcorr.html . The web article links to a