iPhones made in 2014+ have a barometer for real-time elevation tracking. A barometer measures air pressure, which is crucial for calculating altitude changes. The native iPhone Compass app has a built ...

For more than a decade, survey flights have crisscrossed the United States using gravity instruments to calculate a new sea level in an effort that will save the country billions of dollars on ...

Kate Dignan has summited one 14er — she thinks it was probably Longs Peak, but she’s done her best to forget the experience. That trip, and countless photos from hikers around the state, got her ...