Hi LV,
Welcome to PilotAware.
Your Aircraft symbol and heading indicator pointing north when stationary on the ground is perfectly normal. It will turn to its correct heading when you fast taxi for take off, and in flight. I did a lot of early testing in my car and had fun trying to time my approach to prevent it turning to North if I had to stop at roundabouts (not that this was a problem in any way and it very quickly turns back on course when you start moving again).
As you say, SkyDemon using the Tablet GPS will point the correct way on the ground, but SkyDemon can only use a single data source at any one time, so if you switch SkyDemon to ‘Use Location Services’ you won’t get any traffic data from your PilotAware. This is why you need to setup and use ‘Go Flying - Use PilotAware’ for flying (Oh, and the tablet GPS is far less reliable in flight in any case).
Best Regards
Peter