This app is designed as an additional tool for skydiving.It does not replace a barometric and/or audible altimeter.Set the spot and optionally set the wind speed and direction.Secure android device and use a bluetooth or wired headphone.The app should announce when transiting every thousand feet, three minute warning and exit spot.It should instruct when to turn downwind, crosswind and final.Before drifting out of range , it should instruct you to turn back in the direction of the spot.It can also assist in flare timing.Once out of the aircraft, this app should get you back to the landing area and tell you when to flare in total darkness.Some commands you may hear besides altitude when transiting every thousand feet in either direction are: Three minute warning, One minute warning, Green light, Red light and "DEPLOY" if you have gone low.Under canopy you may hear: Keep this heading, Turn left toward target, Turn right toward target, Turn left toward downwind, Turn right toward downwind, Turn left toward crosswind, Turn right toward crosswind, Turn left toward final, Turn right toward final, Prepare to flare and Flare.This app uses less accurate GPS inplace of barometric pressure to determine altitude above ground on old devices without a barometer.This app creates a log file on your device that can be loaded into matlab or python to see a visual 3d representation of your skydive.Also in the log file is a summary of the skydive including "Exit Altitude", "Time in FreeFall" and "Time Under Canopy".Do not rely solely on this app. Skydiving is a dangerous sport!