Why on earth would I want to crowdsource weather prediction? Isn't this one field where we can all agree that an expert opinion backed up by some expensive measurement gear should be a heck of a lot more useful than polling random people? I don't care what my neighbors think the weather will be like this weekend, and I can't imagine why anybody would.
Consider mobile devices as a swarm of sensors. If there are enough devices in an area with barometric pressure sensors, perhaps the data they provide could augment existing weather forecasts. As far as I know the Xoom is the only device with a barometer now but perhaps there will be more.
If we get access to more sensors we'll figure out things to do with them.
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