Feeling a little under pressure? Your iPhone can measure that.
Since Apple introduced the iPhone 6 and 6 Plus in 2014, most iPhones have included a built-in barometer. The first-generation iPhone SE didn’t get the memo, apparently, and is an exception. Apple explained its inclusion as a means of determining relative elevation changes. Without diving too deeply into atmospheric science, iPhones with barometers detect your elevation based on current barometric pressure. The higher up you travel, the lower the pressure, which your iPhone translates into an approximate elevation reading.
Barometric pressure is essentially the force exerted by the air above you. Air molecules have mass, and the more air above you, the more pressure is exerted on you. It’s useful information for determining elevation, but to be clear, barometric pressure also changes with the weather. By itself, the sensor can’t tell if falling pressure means you’re scrambling up a mountain or if storm clouds are rolling in. Apps have to depend on more information, like GPS altitude and local weather station data.
While your phone has all that data to play with, it’s not immediately clear how you, as the owner, can take advantage of it.
Why does Apple include a barometer without a dedicated barometer app?
A standalone app was never the purpose of including the barometer in the first place, nor is that the case today. It’s a contributing feature in most respects, filling in data gaps that other sensors can’t determine. For instance, motion activity, including elevation changes, is used in the Health app for step counting and stair climbing. Similarly, your iPhone’s barometer provides a measurement that other software can use to track elevation changes and determine your location.
Though Apple hasn’t offered a dedicated barometer app, it does allow developers access to pressure and altitude information through Core Motion. They can take that information and build it into fitness and outdoor apps where it will continue to contribute in the background.
It’s also worth noting that Apple’s Weather app doesn’t use the built-in barometer either. Instead, it pulls information from external weather data sources. If you see a barometric pressure reading in the Weather app, that information is not coming from the iPhone’s barometer.
How to check barometric pressure on an iPhone
To view measurements directly from, say, your new iPhone 18, you’ll need an app that explicitly supports the built-in pressure sensor rather than pulling from outside data. App descriptions should lay out all of their sources, so you can easily verify if it’s using the built-in barometer or third-party data.
Barometer & Altimeter & Thermo is a solid option, and it says right there in the description box that it uses the iPhone’s built-in barometer. It also uses GPS and weather station information for calibration. It’s a free app to download, but like most free apps, you’ll have to watch a few commercials and build up a little pressure in your skull while awaiting the results. The listing as of November 2026 requires iOS 13 or later, so as long as you’re not rocking an iPhone 5 from the dinosaur era, you should be fine.
Another option is My Altitude, which also lists that it uses on-device sensors by default when available. Despite misspelling “see” level in its description, it carries a 4.8 overall rating from 27,000 ratings. The free version includes adverts, because of course it does, with in-app purchases to remove them.
Whichever app you go with, take note of the pressure reading before and after walking up a flight of stairs. Then return to the same spot and check weather-related barometric pressure readings so you can compare the two. Just a fun little comparison task to run. Just don’t confuse pressure changes caused by storms or rapidly clearing skies with changes in your current elevation.
