Hi muddy, I don't have that exact app, I have the previous Android Garmin App called Navigon on an S3 & it has an option in settings for HUD support, not sure how it works as I don't have access to a HUD holder to try what it does.
Have no idea how you get your App to do what you want & without a HUD holder to test on, so it seems no point for me to install the new app to test for you.
I have dedicated GPS that I use, so no need for it.
I have used Garmin Navigon on my bike, but that's with direct phone display.
If your lucky forum member Surething will chime in & point you in the right direction.
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