Usefulness of Car Dock App?

[benjamminh]

I wanted to poll the collective wisdom of our august forum regarding the usefulness of a car dock app when the Moto X family has such robust voice controls. I've never used a car dock app so would one be useful considering how much we can do through Moto Assist? Is it enough to put it on google maps for navigation and let Assist do the rest or is there an advantage to a car dock app (music, etc.)? If you do use a car dock app, which one do you use and are you happy with it?