@bentossell You can control music, maps, calling and other functions with Siri. But you can't get a unified interface with navigation+music controls with gesture controls, which are a lot easier to use than voice commands, especially in the car with music playing. I think that if Siri could fully replace an in car experience like Open Road then Apple wouldn't be pushing CarPlay.
The other thing is that you want quick access to functions in the car. In Open Road you can begin navigation & start your favorite playlist in under 5 seconds. When you're starting your drive it's easier & faster to tap these shortcuts in Open Road than it is to use Siri, especially when you're trying to play something like Röyksopp.
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