If you have an android, check the Fdroid store, there are several apps that show you the raw output from every type of sensor on your device. I was surprised to find out several features on mine.

At least since iPhone 6ish? I think Dark Sky was one of the first apps to use it effectively. They'd aggregate the atmospheric data across it's users to make hyper local weather predictions (i.e. "rain in 10 minutes")

I know when I’m looking for a new phone I pay special attention to make sure it has a state of the art barometer

iPhone has had a barometer since 2014.

Yep, mostly just used to help crowdsource weather reporting like this.

Though I have seen another interesting use-case for the barometer, which is for IP-rated (water-resistant) phones, you can use the barometer to check that your device still has a water-tight seal with an app that measures the pressure as you squeeze the sides of the phone together.

I'm glad I wasn't the only one thinking this