Whichever OBD2 adaptor (not the software/app, the hardware you plug in to the OBD port) you use, it must support VPW J1850 protocol. Some do not as I have found out and they won't work on your Blazer.
This one (https://bafxpro.com/products/obdreader) does and is good value.

 

I'm waiting for the shipment. I'll call you when I receive the package.

 

The reader has arrived. It works on every application. Unfortunately, it does not read ABS, drives, automatic transmission, LPG installations. Or I'm doing something wrong.: icon_steer:

 

So now you are connecting with the PCM, correct? If so, the interface is doing it's job. Now you need software application to communicate with PCM to do what you want. None of the phone apps you mentioned will read ABS codes. Auto trans is part of powertrain codes. LPG installations - why would it? Not sure what you mean "drives". As I said before, Car Guage Pro is the phone app that will do the most. It will read/clear ABS codes as well as re ad/clear codes for other modules on the Blazer days bus. It will not read ABS PIDs on a Blazer. Please study about OBD2 to understand the difference and I think you will then understand. What is the problem you are trying to solve?

 

Without starting a new topic maybe someone can help me. This is the first I've seen these BAFX OBDII devices.
I'm wondering if this device and the appropriate software can help diagnose TCCM issues. My first post can actually explain issues more, but I was hoping this method would allow me to send activation commands to the transfer case and help diagnose possible wiring issues. 1998 Bravada AWD

 

AFAIK, none of the apps using bluetooth OBD2 adapters like the BAFX will do anything more with 4WD than read and clear codes. You are asking for bidirectional control of an alternate module (TCCM) on the vehicle data bus. Some say Autoenginuity and Snap-on give a lot of these bidirectional controls, but I have no experience with them. I'm quite sure you can replace both the TCCM and the encoder motor with new for what they cost. The rest of the system just takes a digital volt/ohm meter to check out.

 

Thank you. Now that I know it can't be done I'll move on and try to find a solution.