Exactly as
Acrad posted. Not only can you get live tire pressure but also the tire temperatures.
When I'm airing down/up, I sit in the drivers seat, out of the heat/snow (whichever) in the comfort of my cab and watch as the the tires fill up or air down.
One time off roading with our 4x4 club, between off road trails, we had to be on the highway for a short distance. I was down to about 12 psi in each tire for the trails, and I was watching my tire temperatures while on the road traveling between 40 - 50 mph, making sure they didn't get too hot and blow out. It was very handy having that live info on board.
Note: if you do go with an OBDII dongle and phone app like OBDLink (
OBDLink® - Home - https://www.obdlink.com/), you can only display
1 (one) set of data at a time.
Example: you can be monitoring your engine temps, trans temps 1 and 2, battery, etc,
OR your tire pressure
OR another data set. You can't monitor multiple sets at the same time.
Traveling, I usually have the engine data on, when on the trail, I'll usually be monitoring my tire pressures.