Recently, I have been very curious about the accuracy of the altimeter in the iPhone 6 so I decided to test it by downloading the app "Travel Altimeter Lite", making a small app in Xcode to read the altimeter data off the iPhone's sensor, and then comparing the values from the two apps. And guess what? The altitude as displayed by the app I made was the exact same as the altitude displayed by the app I downloaded (of course the latter was rounded to the nearest meter). I mean, I went up in a tree, I held my iPhone way above my head and way below my feet, but the values in both apps were always the same. The paradoxical thing about all this is that the altimeter app on the app store was last updated on May 14th so its completely impossible that the app accounted for the iPhone 6's altimeter sensor. One more point of interest I asked my friend who had an iPhone 5s to download the altimeter app and he did in fact get a way different value than the one I was getting on my device even though we were standing next to each other. So what gives? Clearly the iPhone 6 does have an altimeter, but I'm still curious as to how this app is able to read the data off the new iPhones. Did Apple simply not record that it was in fact updated?