Recently I have started using audio route navigation while biking. It works well, but I have a couple of suggestions.
It would be nice to have a warning message or sound when a wrong turn is made and you are off course. A bipping sound just to make the user know, that you are not on the planned route anymore.
Moreover, when you then stop to check the map, the arrow turns automatically in the correct direction, not the one you were really following while moving. This creates some difficulty when trying to assess where you were going in relation to the correct direction.
Thanks for everything (and allow us to download the gpx file of the track).