Existing Google Maps voice commands like "What's my ETA?" work too, plus new addition like the ability to turn traffic display on or off. You can control whether or not the phrase works on your phone via settings in the Google Search app (make sure you have the latest version for that and Maps first), to turn on "Ok Google" everywhere, or just in Maps, if you'd prefer it that way. You can find a list of commands here, or just give it a try and see what works.

Whether or not you use the voice commands, it's another example that while the Google Now / Now on Tap branding may be taking a backseat, the features are actually spreading further throughout the OS. Google's new Assistant AI helper is built around conversational responses to any "Ok Google" query, and we're expecting to hear more about it during the October 4th "Made by Google" event.