Where is the barometer on the iPhone?

How to open the barometer on an Apple phone:

1. You can go to the App Store to download the Barometer for iPhone 6 / 6 Plus application.

2. Enter your Apple ID account and password, as shown in the picture

3. After downloading and installing, open the application and you will see the screen in the picture below

In summary, the barometer is installed and opened.

The function of the barometer in the mobile phone:

A barometer is used. In fact, the basic function of the barometer is to measure the pressure of the atmosphere. So why do we need to install a barometer in the mobile phone? What is it used for? A Google engineer's explanation may be more professional - the purpose is to make full use of the function of three-dimensional space to assist GPS; to judge the height of the device through the level of air pressure, and then use the longitude and latitude obtained by the GPS to calculate faster Find the location of the device.

Theoretically, GPS is a four-dimensional system that can obtain a three-dimensional space coordinate and a time coordinate. In fact, most wireless communication base stations now obtain time through GPS (which is crucial in synchronous communication systems). However, a major disadvantage of GPS is that it takes up to several minutes to accurately locate your geographical coordinates. Therefore, in order to solve this problem of GPS, people use various methods to assist GPS positioning. The most common method now is to use A-GPS and barometer.

One thing that needs to be pointed out here is that the barometer does not measure the specific air pressure value, but only the change in atmospheric pressure. The advantage of this is that it is independent of local weather conditions - as long as it keeps track of changes in air pressure, it can calculate your altitude.