This altitude calculation tool will provide you with the most accurate altitude values available for any location on the globe simply by tapping on a map. Altitude values are obtained from local and international land survey databases and are more reliable than GPS altitude values. Tap any two locations on the map and get the rise or drop (delta altitude), delta distance, grade, and percent change in elevation. Now, when you tap on a body of water, the depth below sea level is returned. Also includes a reverse geocoding tool to get address information for any location that you tap.