If you wish to use your phone for navigation I would suggest installing one of those screens that mirror your phone on the motorcycle. Not only will you have access to all of the features of your phone but it will be on a much bigger screen. This way you still get to use your phone and your phone stays in your pocket safe from the weather and the vibration.
The below are just examples that I pulled at random. These units can be had much cheaper if you don't include things the front and rear cameras, built-in cell network connectivity, etc., etc.
There was also at least one discussion about this option-
Carpuride ? anyone used this yet?
Carpuride is one example-
Carpuride Car Play Screen.
Chigee is another-
AIO-5 lite Motorcycle Smart Riding System.
Can anyone guarantee you that your phone will always be safe in your pocket, that it will always stay there, and that it will still work after a crash and allow you to make that emergency call for help 100% of the time? Of course not, anyone who believes or makes that claim is a fool. If you do not have access to your phone because it is not on you however, and you can't get to it after a crash, in those circumstances you are guaranteed that you will not be able to make that call 100% of the time.