Your HUDWAY Drive device will not work without your smartphone and HUDWAY Drive app.
You'll need the app to find HUDWAY Drive and connect to it, as well as to set up what to display on the HUD — and for the navigation to work.
The Drive has no GPS modules, which is why it's the HUDWAY Drive app monitoring your location using your powerful phone electronics. And it's the app that listens to (after you've allowed it) which push notifications are coming and who's calling you — and then sends this data to the Drive.
Also, it's the app that knows when the scanner is connected to unlock OBD-related widgets (for example, RPM, fuel level, or speed). The article about displaying OBD Data is here: Fetching OBD-II data to HUDWAY Drive