No, it and of itself won't be meaningful. That's the crowdsource bit.
OK, for all of you that stare at the weatherperson and wonder what the funny lines are for: The column of air just above your head and extending to the top of the atmosphere has a mass that depends on a number of details. This fluctuates from minute to minute and, in fact, occurs in waves (those funny lines). Detailed information about the barometric pressure at any given location and time can be sent to a central station where that data is collected and displayed. The more (accurate) sensors that you have, the better detail and, presumably, the better quality of weather (not climate) forecasting.
Having lots of barometric pressure measurements attached to a device that can accurately determine location and time can be a useful source of data. For the National Weather Service, the National Security Agency and other fun TLAs. The utility for the weather service is obvious, for the NSA not so much but I believe it has to do with overall conductivity of aluminum foil, or something along those lines.