Barometer Plus app measures air pressure and altitude using your device's built-in barometric pressure sensor. Because air pressure changes usually indicate a weather change, you can use this app to monitor and predict short-term weather variations. People suffering from migraine, headaches, or joint pain can monitor how barometric pressure impacts their mood. Fishermen can monitor the atmospheric pressure for right-time fishing. FEATURES: • The app contains a barometer and altimeter with a personalization graphic in classic analog style. It also displays the current temperature and humidity. • Display barometric pressure (sensor value) or mean sea level pressure (MSLP - value used in weather forecast services or stations). • Units support for pressure: mb, inHg, kPa, atm, Torr, psi, hPa, mmHg. Units for altitude: meter, feet. • Calibrate the barometer using altitude/location from the GPS. Calibrate the altimeter using the nearest airport information/METAR, or manually enter the QNH of the nearest airport. Offset sensor output value. • Measure the height (building/mountain/hiked/climbed) using the "Relative Altitude" feature (can be enabled in the app's Settings). • Notification about pressure change. "Notification custom rule" for you to define how and when the app sends notifications. Notify when air pressure changes indicate that extreme or worse weather may occur. • "Pressure Tracking" and "History Graph" require "Background App Refresh" or "Always Location Service" with "Exact update interval" enabled. • "My Area" allows you to define your frequent stay places, and the app tracks air pressure with location data. • Export history to CSV format and Today widget. • This app is the digital version compared with an aneroid or mercury barometer and can be adjusted to MSLP with additional features. CUSTOMIZABLE: You can change your barometer/altimeter appearance with: • Seven different housing colors. • Black, white or blue disk background. • Four different app backgrounds. • Three different types of needles. • Marker needle for easily monitor. • Dark or light Today widget theme. NOTES: • App only works on devices with a barometer sensor, such as iPhone 6/6s/7/8/X/11/12/13 (including Plus models), iPad Mini 4/Air 2/Pro, or later. • Weather icons on the dial: This only shows the air pressure trend like in an analog barometer. • Each time your device reboots, open the app for tracking with the "Exact update interval" feature work. • You may take the phone/tablet far away from computers, cables, and other magnetic sources to get accurate results. • This app is Pro / Premium version of the "Barometer Plus - Altimeter" app, only difference is all feature unlocked and no ads. If you already use the "Barometer Plus - Altimeter" app and purchased in-app, do not need to purchase this again. We welcome your ideas and suggestions - please email us at: [email protected]. Follow our official Facebook page: https://www.facebook.com/barometerplus/ or Twitter account: https://twitter.com/pvdapps.