Final Asgard

Hey guys. My RC car came with a TQi controller, which has the ability to hook up my iphone to it and use an app to track the speed of the car as well as other information.

What I am wondering, what parts do I need at a minimum to pull this off?

I know I need the dock, of course, and the TQi receiver. What else do I need to get the speed? And what other important information should I get sensors for?

I have been looking for a list to explain this to me but am coming up short.

thanks!