This is a very good barometer and altimeter app for the Apple Watch, iPhone and iPad. It uses the integrated barometer hardware in those devices. No internet connection needed. However there are some missing features that could add value to this app : - display of the air pressure at sea level - hPa display unit option - Watch OS 5 complications to display air pressure and altitude (corner and others notifications types) - saving of a specific measure (altitude and air pressure) in order to show air pressure evolution between 2 measures. - a preference pane on iPhone and iPad would be welcome