There's a whole lot of ways to do this. But here's a cheap way to just try it out.
You need an OBD2 dongle. This is probably the hardest part, because there are so many poorly made, crappy parts out there. Finding a good one can be tough. I've used this one in the past, and it's worked ok. I've got a much nicer adapter now, but that's because I hack on these things as a hobby and I needed on with some advanced features.
https://www.amazon.com/Vgate-Bluetooth-Diagnostic-Scanner-Check-Android/dp/B07DCHWP9P
Then you need a copy of Torque Pro for Android. That's $5 on the Google Play store. It's not available for Apple devices. I'm sure there's something similar, but I'm not an Apple guy, so I can't make any recommendations.
You'll need a charger and cradle if you don't already have them. That's another thing where you can spend $5 or $50. It's totally up to your preferences. I just set mine in my dash tray for a quick test. That's why the pitch meter is so far off level. It uses the phone's internal sensors for that.
I don't want to derail this thread by going too deep into the details, but the setup is pretty easy. You hook the dongle to your car's OBD port, pair the phone with it via Bluetooth, launch the app and pick which gauges you want to see. Torque even has a whole set of pre-defined GM gauges, which is how I got the oil and trans gauges to show up.
Another added bonus is you can use this on pretty much any car you have that's newer than 1996. You can check and clear codes, log performance data, and troubleshoot problems. It won't do everything a Tech2 will do, but it's still an unbelievable value for the money.
