Barometer has the role to measure air pressure. This reading is important because it helps your iPhone determine altitude, as well as relative elevation changes. This way your iOS device can track your vertical movement, without the need of GPS assistance. More, it transforms your iPhone in an actual barometer, because air pressure reading is used for weather forecasting!
How To Use iPhone Air Pressure Readings
This new sensor opens up a lot of important features for iOS users. Developers have already released new apps and adjusted current ones to be able to access, keep track and efficiently use your iPhone’s air pressure readings.
They are usually recorded using the hectopascal (hPa) unit and can be used to determine elevation, forecast weather and even track the number of stairs climbed:
1. Elevation Estimation
Your iPhone reads the current air pressure and compares it with the sea level value to calculate your current elevation. You can also obtain relative altitude readings by setting altitude to 0 feet (or meters) when on ground level. Then let your iOS device show you how much you climbed when you’re at the 20th story of a skyscraper. The great thing is that these readings are adjusting almost instantly, so you can actually track your elevation as you’re in the elevator. And, yes this is done without a GPS, so don’t worry about lack of signal!
2. Weather Forecasting
Old school weather forecasting can be accomplished with an iOS Barometer app. In meteorology significant pressure change means, also an alteration of weather. If air pressure drops suddenly, it signals that a low pressure system looms at a horizon and there are increased chances of rain. On the other hand, fast pressure raises are the equivalent of sunshine! Any change of 3.5 hPA or greater in air pressure is forecast of changing weather. Thanks to the barometer sensor you can easily let your iPhone track these readings and be your own meteorologist.
Update: Dark Sky is one of the first iOS weather apps that uses the iPhone 6 and iPhone 6 Plus barometric sensor for forecasts based on crowdsourcing!
3. Physical Activity Tracking
Step counters have already implemented iPhone’s barometer readings and are now able to keep track of your physical activity, even on the vertical. This was possible prior to iPhone 6 and iOS 8 only with the help of the GPS. But using this system around the clock, significantly reduces battery life and exposes the user to additional electromagnetic field radiation. Now, with the help of the barometer sensor, this extra load is removed from the A8 chip and your pedometer can easily track your stair climbing 24/7 and show your progress whenever you slide down the iOS Notification Center.
iPhone Barometer Sensor Apps
Here are a few iOS apps that use your smartphone’s built-in barometer sensor to accomplish the functions described above. We’ve tested them out for you and here are the results:
1. Barometer & Altimeter (Weather, Elevation) – Another great free app that estimates elevation and also predicts the weather, while analyzing your iPhone’s air pressure readings. As a bonus it offers widget integration for iOS 8 users.
2. Pedometer++ (Movement Tracking) – A simple and very efficient step counter that tracks your movement 24/7 and counts the amount of steps you made. If you own an iPhone 6, it will also track the amount of stairs climbed and transform them in floors. Accuracy is pretty good. We’ve tested it on a ten-storey building and Pedometer counted 9 floors for me. Widget function is included!
3. Barometer plus Altimeter (Weather, Elevation) – This one is similar to the first placed app in this list. The minus comes from the lack of widget support. If you’re not an iPhone 6 user yet you have to use the GPS based altimeters.
4. Barometer + Altimeter (Air Pressure, Elevation) – Is one of the simplest software available. It provides air pressure readings and can measure relative altitude, which means that you can measure how much you climb or decline, when setting a desired location as starting point.