Most new-ish Android phones have a barometer. It assists in determining a rough altitude to make GPS lock faster. Hence the ability to use apps like this to tr

Most new-ish Android phones have a barometer. It assists in determining a rough altitude to make GPS lock faster. Hence the ability to use apps like this to track barometric pressure across smartphones and track trends: https://play.google.com/store/apps/details?id=ca.cumulonimbus.barometernetwork&hl=en https://play.google.com/store/apps/details?id=ca.cumulonimbu...