Publishing beta A new operating system version before new hardware is released always carries a risk. The operating system already contains some information that reveals what the new hardware will offer, and it is only a matter of time before developers discover it. Now, developers have managed to discover it in the new API in iOS 8 interesting string of code called “isRelativeAltitudeAvailable”. The code carries information about measuring atmospheric pressure, and the barometer can be used to monitor the weather as well as altitude.
According to sources, the company is working Apple to a new, modified version of the Compass app that offers altitude information. Apple originally added the Compass app to iPhone 3Gs, which is the first in the company's line of phones Apple offered a digital compass. Interestingly, due to the altitude, he could Apple easily also measure the calories burned and the intensity of your fitness activities, depending on whether you run uphill or flat.
*Source: macrumors.com
Altitude can also be determined from GPS, so sports trackers have been using it for a long time. But it would also be possible to use the barometer inside buildings.
I'm curious about the accuracy.
What if apple neurowhite watch but iPhone 6 will offer all the sensors that should have been in the watch? :)