i just installed my naviplus - didn't see a gps antenna in the box, unless I am missing something. I used Gaia maps the day after install and it seemed to track me just fine on a 4 hr remote trail.
So what did you do? connect an android device just for the maps and not use carplay?
Mine is an older version of the Naviplus. It is more like the current EC Offroad version (Lsailt box running android operating system). This version has an external GPS antenna.
if you run it without a phone connected, it boots to an Android OS. If you have a phone connected, AutoKit will have it boot to the appropriate car solution (CarPlay if it is an Apple device, and Android Auto if it is an Android device).
Mine usually starts with CarPlay since I use an Apple iPhone. However, from the CarPlay menu, there is a button that lets you jump into the onboard Android computer screens (the Lsailt box is just a simple computer running an Android operating system). If my phone isn’t in the car, and I pres the nav button for 2 seconds, it also boots to the Naviplus ndroid user interface.
Once on the Naviplus Android OS, it isn’t using the iPhone for anything (connected or not).
From there, I selected the Google Play icon, entered my Google username/password and searched for Gaia GPS. Then I clicked the button to install it. From there I just had to click the Gaia icon, and it opens up.
GPS antenna circled in red: