I wrote that software, called SeisMac. Someone figured out the Apple-private API for the Sudden Motion Sensor that parks your laptop's hard drive if it detects free-fall. Working from that, I wrote a free app that used the API to show three-axis acceleration graphs. I was proudest of the calibration utility, which had you tip your laptop on its side (with properly rotated dialogs!), and then on its screen.
People would send me recordings from all over the world (e.g. on a ship in the Drake Passage showing enormous surges). It was a lot of fun, and I even got an educational grant to improve it.
Big bummer when Apple switched to solid-state drives (well, a bummer for my one small reason...)
I used an iPhone as an air pressure recorder. There's an app for that; many actually. Anyways, the trunk gate on my car wasn't sealing and when it went over pavement joints on the highway it would slightly open and then close in quick succession which was nauseating. I showed the data to Tesla service and they (grumbled and) readjusted the trunk gate. The problem disappeared.
Reminds me of the people who used their ThinkPad's vibration sensor to detect smacks on the machine, and rigged their X window manager to switch virtual desktops when smacked from the appropriate side, panning right when smacked on the left, and left when smacked on the right.
I heard that IBM decided to move out of this building [1] because vibration due to the construction of the tower across the street kept destroying hard drives in their computing center.
https://allthegooddomainsweretaken.justinmiller.io/2007/04/0...