Apps in this category may contain mild or occasional cartoon, fantasy or real-life violence, as well as occasional or mild adult, sexually suggestive or horrifying content and may not be suitable for children under 9 years of age.

12+

Apps in this category may contain occasional mild indecent language, frequent or intense cartoon or real-life violence, minor or occasional adult or sexually suggestive material, and simulated gambling, and may be for children under 12 years of age.

17+

You must be at least 17 years old to access this App.

Apps in this category may contain frequent and intense offensive language; Frequent and intense cartoon, fantasy or realistic violence: frequent and intense adult, scary and sexually suggestive subjects: as well as sexual content, nudity, tobacco, alcohol and drugs, may not be suitable for children under 17 years of age.

Altimeter X Screenshots

iPhone

About Altimeter X

iOS/GPS altitude
Altitude estimated by the device's location service. It works reasonably well in most situations but can't track small changes and can be unreliable indoor.

Barometric altitude (iPhone 6 minimum)
Altitude based on the device's barometer. This is how most hardware altimeters work. It can track very small relative variations but must be calibrated with weather data or GPS. Calibration with weather data grabs current sea-level pressure and temperature at your location from a nearby weather station. GPS calibration takes the current iOS/GPS altitude as a starting point then uses the barometer to track changes.

Elevation database
This method displays earth surface elevation at your location by polling an elevation database. It works even with very imprecise location data but requires network access. Surface elevation usually includes buildings and trees.