LocationHelper that and GPS DMS converter.

gistfile1.cs

public static class LocationHelper {
    public static async Task<Geoposition> GetCurrentPosition() {
        Geolocator locator = new Geolocator();
        return await locator.GetGeopositionAsync();
    }

    public static async Task SavePosition(StorageFile file, Geoposition position) {
        DMS latDms = new DMS(position.Coordinate.Latitude, Coordenate.Latitude);
        DMS lonDms = new DMS(position.Coordinate.Longitude, Coordenate.Longitude);

        int[] latitude = new int[] { latDms.Degrees, latDms.Minutes, latDms.Seconds };
        int[] longitude = new int[] { lonDms.Degrees, lonDms.Minutes, lonDms.Seconds };
        int[] denominator = new int[3] { 1, 1, 1 };

        List<KeyValuePair<string, object>> extraProperties = new List<KeyValuePair<string, object>>();
        extraProperties.Add(new KeyValuePair<string, object>("System.GPS.LongitudeNumerator", longitude));
        extraProperties.Add(new KeyValuePair<string, object>("System.GPS.LongitudeDenominator", denominator));
        extraProperties.Add(new KeyValuePair<string, object>("System.GPS.LongitudeRef", latDms.Direction.ToString()));

        extraProperties.Add(new KeyValuePair<string, object>("System.GPS.LatitudeNumerator", latitude));
        extraProperties.Add(new KeyValuePair<string, object>("System.GPS.LatitudeDenominator", denominator));
        extraProperties.Add(new KeyValuePair<string, object>("System.GPS.LatitudeRef", lonDms.Direction.ToString()));

        await file.Properties.SavePropertiesAsync(extraProperties);
    }
}

public enum Coordenate {
    Latitude,
    Longitude
}

public enum Direction {
    N,
    S,
    E,
    W
}

public class DMS {
    public DMS(double value, Coordenate coordenate) {
        this.SetValue(value, coordenate);
    }

    public double Value { get; private set; }
    public int Seconds { get; private set; }
    public int Degrees { get; private set; }
    public int Minutes { get; private set; }
    public Direction Direction { get; private set; }

    private void SetValue(double value, Coordenate coordenate) {
        this.Value = value;

        if (coordenate == Coordenate.Latitude) {
            if (value >= 0) {
                this.Direction = Direction.N;
            }
            else {
                this.Direction = Direction.S;
                value = Math.Abs(value);
            }
        }
        else {
            if (value >= 0) {
                this.Direction = Direction.E;
            }
            else {
                this.Direction = Direction.W;
                value = Math.Abs(value);
            }
        }

        this.Degrees = (int)Math.Floor(value);
        this.Minutes = (int)Math.Floor((value % 1) * 60);
        this.Seconds = (int)Math.Round((((value % 1) * 60) % 1) * 60);
    }
}