Samsung's Galaxy Nexus is the most high-profile device to date to feature a barometer amongst its guts. Seems strange that a atmospheric pressure measurement would be crammed in a device where space is supremely valuable, right? Except it's actually wonderful.
Traditionally, barometers have been used to detect—and predict—short term changes in weather. Measured drops in pressure indicate rain is on the way. Sharply rising pressure signals clearer skies are ahead. But surely, Samsung and Google didn't conspire on this just to make more accurate weather predictions, right? Actually, maybe. But that's just part of it.
What if the barometer was used not to provide personalized weather predictions, but to provide data to a crowdsourced weather network for the common good of commuters/travelers/pedestrians everywhere? Imagine having a server interpret thousands of pressure readings in a small radius to give you very specific, very precise weather forecasts.
I'd like to imagine that such an idea would work best in a moderate-to-dense population area where there was a pretty constant and solid mesh net of barometric readings. How many phones would be required in a given area to accomplish this? According to the NY Times, the most prominent weather app that employs crowdsourced data is Weather Underground. They currently pull from 20,000 stations across the country. With a barometer in every phone? They could be pulling from 20,000 barometric sensors in a single neighborhood or city.
There's also an app in the Android Marketplace called pressureNet, which currently logs barometric data from Motorola Xooms (which also have the sensor) and plots the info on a map. Once they have more users and more data, they promise to use the data to provide weather insights. But given that the app is all of 10 days old, its usefulness remains to be seen.
There are privacy concerns at play here—when aren't there? Such an app would have to collect your location along with the barometric data for it to matter at all. And in all likelihood, Google would have access to this data, which rightfully worries some.
But for others, location is exactly why a barometer will be most welcome.
The other popular use for barometers? Navigation. GPS is great when you have a clear shot of the sky, but when weather is bad, or you're in the city of a cramped metropolis, things get a bit dicey. That's why accelerometers, wi-fi chips and, yes, the barometer, have become increasingly useful in navigation, able to help assist the GPS in determining location.
The barometer uses its atmospheric pressure readings to determine your altitude and more accurately determine how quickly you're moving through an area. Considering that smartphones have all but made the standalone GPS navigation device obsolete—and that Android houses one of the better navigation apps around—it would make sense that Google would want to put time and effort into making that technology even better.
Outdoorsy-type apps could become more useful to hikers and adventurers for whom topography matters.
Here's the other thing: once devs get their hands on Ice Cream Sandwich and its barometric possibilities, who knows what they might come up with? The most obvious secondary benefit might be to gaming developers, who could use the altitude measuring to improve control schemes in games. But what's most exciting are the possibilities we can't even dream of yet. And it's something no one else has right now.
So yes, the introduction of a barometer may have made a few eyes roll. But at the very least it could revolutionize the way we think of weather predictions and navigation. And at most? We'll find out soon enough.
Update: Sadly, one of the scientists at Weather Underground, John Celenza, doesn't think the idea can work so well.
According to Celenza, barometers are too sensitive to changes in altitude to provide reliable readings on the move. He says that you'd have to be able to subtract a variety of variables to get any sort of usable reading. Furthermore, he says that barometric pressure doesn't change much over relatively small surface areas. For example, his weather station is keyed into readings from San Francisco International Airport over 10km from his house, and he says that the difference in pressure is negligible. He believes a wind speed sensor would be more useful for crowdsourcing weather from a smartphone, but says that tech like that is too expensive for mainstream implementation. He figures that the main reason for the barometer is navigation and little else.
That said, we like to hold out hope that someone could potentially develop a way to work around the altitude limitations of the barometer.