MapAcitivity.java

 @Override
    public void onConnected(@Nullable Bundle bundle) {
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            // TODO: Consider calling
            //    ActivityCompat#requestPermissions
            // here to request the missing permissions, and then overriding
            //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
            //                                          int[] grantResults)
            // to handle the case where the user grants the permission. See the documentation
            // for ActivityCompat#requestPermissions for more details.
            return;
        }
        Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);

        if (location == null) {
            LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);

        } else {
            //If everything went fine lets get latitude and longitude
            currentLatitude = location.getLatitude();
            currentLongitude = location.getLongitude();

            Toast.makeText(this, currentLatitude + " WORKS " + currentLongitude + "", Toast.LENGTH_LONG).show();

            marker = mMap.addMarker(new MarkerOptions().position(new LatLng(currentLatitude,currentLongitude)).title("Current Location"));
            CameraPosition cameraPosition = new CameraPosition.Builder().target(new LatLng(currentLatitude,currentLongitude)).zoom(14.0f).build();
            CameraUpdate cameraUpdate = CameraUpdateFactory.newCameraPosition(cameraPosition);
            mMap.moveCamera(cameraUpdate);
            runnable.run();
        }
    }
 
 @Override
    public void onLocationChanged(Location location) {
        currentLatitude = location.getLatitude();
        currentLongitude = location.getLongitude();

        Toast.makeText(this, currentLatitude + " WORKS " + currentLongitude + "", Toast.LENGTH_LONG).show();

        // TODO : Animate your marker to this new latlong of device
        // animateMarker(marker,new LatLng(currentLatitude,currentLongitude),false);

    }

public void animateMarker(final Marker marker, final LatLng toPosition,
                              final boolean hideMarker) {
        final Handler handler = new Handler();
        final long start = SystemClock.uptimeMillis();
        Projection proj = mMap.getProjection();
        Point startPoint = proj.toScreenLocation(marker.getPosition());
        final LatLng startLatLng = proj.fromScreenLocation(startPoint);
        final long duration = 500;

        final Interpolator interpolator = new LinearInterpolator();

        handler.post(new Runnable() {
            @Override
            public void run() {
                long elapsed = SystemClock.uptimeMillis() - start;
                float t = interpolator.getInterpolation((float) elapsed
                        / duration);
                double lng = t * toPosition.longitude + (1 - t)
                        * startLatLng.longitude;
                double lat = t * toPosition.latitude + (1 - t)
                        * startLatLng.latitude;
                marker.setPosition(new LatLng(lat, lng));

                if (t < 1.0) {
                    // Post again 16ms later.
                    handler.postDelayed(this, 16);
                } else {
                    if (hideMarker) {
                        marker.setVisible(false);
                    } else {
                        marker.setVisible(true);
                    }
                }
            }
        });
    }