Ergonomic Altimeter

You need the height, not a map full of buttons. Altimeter puts one number on the screen: metres above sea level. GPS reads altitude on the device chip. A barometer, if the phone has one, keeps the number alive between fixes — after you calibrate from GPS or a trail marker. Vertical speed sits under the pressure. Accuracy is visible: vertical, horizontal, satellites, source. It works where the network does not. The mountain profile uses the chip only. Airplane mode with GPS on is enough. City adds network and fused for a faster first fix. Battery stays quiet and only copies a position another app already has. Auto starts on the chip and asks the network if GNSS stays silent. Continuous GPS tracking (on by default) keeps the chip in navigation mode, about one reading a second. Turn it off when you want the battery more than the tick. No account. No ads. No track uploaded anywhere. Settings and calibration stay on the phone. The internet is only an optional check for a newer version in Play — a banner you can dismiss. Altitude never uses the network.