I imagine that it is just Samsung's wrapper round the standard Android/Google voice recognition stuff.
The nature of Siri, Androids VR (has it got a 'friendly' name), Cortana, is that they all rely on a backend servers to do the grunt work and so you end up passing info off to Apple/Google/MS.
I use Llama, which can do similar things. I'm not really bothered about needing to use my phone whilst driving enough to try to get something working though.