It could not be easier:

- Install on your android phone NavGarmin
- Install on your Garmin device the Connect IQ application Maps Nav (https://apps.garmin.com/en-US/apps/ac9022d5-274b-4515-a1e5-1c2164c05202)
- Launch a navigation via Maps
- Launch Maps Nav application on your device, this one will receive direction notifications automatically.

And here is nothing simpler.

For any remarks or bugs send me an email

*Known issue: Maps Notifications must be enabled for the app to work