Yeah, that doesn't make any sense. Barometers are only good for detecting relative altitude/elevation changes over short periods of time. Over longer periods

Yeah, that doesn't make any sense. Barometers are only good for detecting relative altitude/elevation changes over short periods of time. Over longer periods of time (hours/days) the atmosphere pressure is going to change whether you change altitude or not. Over short periods, the barometer can give a relative change. Without a known starting point, it can't give you absolute altitude/elevation. It has nothing to do with getting a gps lock. I'd be pretty surprised if the phones didn't pull down the satellite constellation data over the network vs waiting on the nav message broadcast from the satellites.