Pilot: Aviation Altimeter for Android

11 things about Pilot: Aviation Altimeter

1. A pressure altimeter is incomparable to some apps that determine your altitude by using only ASTER and/or GPS.

2. Since air pressure at the same location with the same altitude varies everyday due to different weather conditions, the variation would cause a small error in altitude reading.

3. The principle is that the higher the altitude, the lower the air pressure (in other words: the higher the altitude, the thinner the air which makes it hard to breathe; the lower the altitude, the more “abundant the air is”).

4. At 35,000 feet, it was measuring the cabin altitude, which is what a real altimeter would measure inside the plane [...] Tonight it worked just perfect, I recorded it as we were climbing and the cabin altitude as well." --- David, Airbus captain.

5. It uses your iPhone’s barometer (air pressure sensor) to detect the surrounding air pressure hence determine your altitude.

6. GPS is not accurate in determining true altitude, which often results in ~100m (~300ft) error; while ASTER is a library of elevation maps of the Earth.

7. That’s how air pressure is used to determine altitude.

8. It is a real pressure altimeter using the built-in air pressure sensor (barometer) in your iPhone.

9. Although it is designed and engineered for best accuracy, this is NOT a FAA certified flying instrument hence it should NEVER be used for flying or other high-risk activities such as skydiving, hang gliding, hot-air-ballooning etc… Always use certified instruments for the high-risk activities, do not use this app as a replacement.

10. Pressure altimeters, also used in professional aviation, are among the most accurate types of altimeters.

11. Being a map library, ASTER is problematic when you are not on the ground surface of the Earth— for example in an underground cave, inside a high-rise building, on a hot-air balloon…etc.