Organic Maps is the most private offline map app, it looks prettier than Google Maps and Apple Maps, it leverages data from openstreetmap that you can update easily compared to the competitors, it’s very battery efficient and the best of all its FOSS.
Can I talk to it while I’m driving?
Sure! Do you need it to react in any way at all?..
More seriously though, there’s a microphone button for the search box, which uses the Google Speech service on my phone. It doesn’t seem like it does a lot with speech though.