Glass is a perfectly fine way to get directions while driving. Just listen to the voice prompts and ignore the screen. Heck, one can push the prism up to the

Glass is a perfectly fine way to get directions while driving. Just listen to the voice prompts and ignore the screen. Heck, one can push the prism up to the top of your head so there's no chance to see it. (To be sure, one can also do this with a GPS app on a smart phone, but having left a phone behind in a rental car, I see value in using a device that's attached to me.)