I was just thinking about this. A talking smart watch that gives turn by turn directions might be a useful thing. Is there a good cheap(ish) android watch that talks? Then again I usually ignore turn by turn directions if using my phone for a GPS, as the directions given by Waze or Googlemaps or whatever apps are not practical in LA traffic (impossible left turns, etc). It's more useful to have a map that shows you the bigger picture, so I can see the appeal of having the phone (or discrete graphic GPS) mounted on the bars. Not sure it'd be a good idea going through rougher neighborhoods though.

Briefly tried Ride With GPS on my old phone and didn't like it for some reason. Perhaps I'll give another shot.