Google Maps shows constantly rotating direction despite other compass apps working correctly
Same issue here on my Galaxy S-6 Edge Plus.  The blue dot/shadow spins rapidly.  Master reset did not fix.  Verizon actually replaced the phone and the new phone acts up as well. I went to Best Buy Samsung help desk and they mentioned an issue that is going to be corrected (soon) as an update to Google Maps. I hope this rapid spinning doesn't mess up any of the sensors on the new phone...