I have the Bluefire data adapter. It basically reads the information from your ECM and bluetooth connects to the app.
I too have a 7.3 (2000) and honestly, I'm a bit disappointed in the amount of data that the Bluefire provides, at least out of the box. I haven't dove into all it can do, but my preliminary research using the app shows it's got a lot more information for newer vehicles. This makes sense, because the ECMs have more information to provide.
You might want to check out what all your ECM provides and match that up to what parameters the Bluefire is set to read.
If you have a TCM for your tranny, and it coordinates with the ECM, you might get some of that info too. I have no TCM, so I'm not sure about that.
If you have a RE bus, hopefully you have a rear and front data port. I plug mine into my front data port and the signal has to travel an amazing 1' to my phone.
Per the bluetooth cameras, I haven't researched them yet.
What is the transmission range on those?
Can the apps deal with multiple cameras? I'm thinking front dashcam, side mirrors use.