Future location data will include all three data points.
Currently through GPS, phones can detect our latitudes and longitudes — basic data in determining location. But with sensors like altimeters, phones will be able to detect our elevation — this is big. Altimeters are coming soon to phones and other devices, bringing some very interesting opportunities.
A simple use-case would be during running — you would be able to measure the elevation of your runs. Combined with distance and speed data it should also calculate your calorie burns better. This sensor would be great for Jawbone’s UP and Nike’s Fuelband.
Larger use-case — mapping your location in 3D. What if your phone could tell you exactly where you are in a building?
This requires all three of these data points to be overlaid on a building’s schematics and have that aggregate be made public on places like Google maps. Take an office building for example — by having these data points on a building’s schematics and with a phone that has GPS and altimeter, you can now find your location not just in latitude and longitude but elevation as well — meaning you can see which floor you are on as well just from your phone.
I see this being very useful in shopping malls, airports, office buildings, hotels etc. Let’s say you’re in a mall, now your phone will be able to show you your location there in 3D — making it easier for you to see where exactly you are (including your floor) and shops that are on your floor — helping you navigate.
For checking friends’ location this would be awesome (also super creepy). Assuming people want to share their location this precisely, in hotels it can help you discover that a friend is staying two floors down. Or during emergency, you can share your location to notify emergency personnel exactly where you are in a building — saving them precious time in search.
Location data this precise should be handled and shared very carefully. You don’t want this to happen.