Android Question Invalid marker position on googlemap

[Pooya1]

Hi
I have many location that i show their with Polyline on googlemap and it is correct
I try use bearing for marker direction on googlemap but is is not exact
My code for get bearing marker (marker direction)

Sub GetDirectionLocation(StartLocation As LatLng,EndLocation As LatLng) As Float
    
    Dim angle As Float
    angle    =    finalBearing(StartLocation.Latitude, StartLocation.Longitude, EndLocation.Latitude, EndLocation.Longitude)
    Return angle
    
End Sub

Private Sub finalBearing(lat1 As Double,long1 As Double,lat2 As Double,long2 As Double) As Double
    Return (bearing(lat2, long2, lat1, long1) + 180.0) Mod 360
End Sub

Private Sub bearing(lat1 As Double,long1 As Double,lat2 As Double,long2 As Double) As Double
    
    Dim degToRad,phi1,phi2,lam1,lam2 As Double
    degToRad = cPI / 180.0
    phi1 = lat1 * degToRad
    phi2 = lat2 * degToRad
    lam1 = long1 * degToRad
    lam2 = long2 * degToRad
 
    Return ATan2(Sin(lam2-lam1)*Cos(phi2),Cos(phi1)*Sin(phi2) - Sin(phi1)*Cos(phi2)*Cos(lam2-lam1)) * 180/cPI
        
End Sub

 

[Erel]

You can use the Location object from the GPS library to make these calculations (DistanceTo and BearingTo).