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diff --git a/examples/mobile/qtbubblelevel/accelerometerfilter.cpp b/examples/mobile/qtbubblelevel/accelerometerfilter.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the demonstration applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <math.h>
+#include "accelerometerfilter.h"
+
+#define RADIANS_TO_DEGREES 57.2957795
+
+AccelerometerFilter::AccelerometerFilter()
+    : x(0), y(0), z(0)
+{
+}
+
+//! [0]
+bool AccelerometerFilter::filter(QAccelerometerReading *reading)
+{
+    qreal rx = reading->x();
+    qreal ry = reading->y();
+    qreal rz = reading->z();
+
+    qreal divider = sqrt(rx * rx + ry * ry + rz * rz);
+
+    // Lowpass factor
+#ifdef Q_OS_SYMBIAN
+    float lowPassFactor = 0.10;
+#else
+    float lowPassFactor = 0.05;
+#endif
+
+    // Calculate the axis angles in degrees and reduce the noise in sensor
+    // readings.
+    x += (acos(rx / divider) * RADIANS_TO_DEGREES - 90 - x) * lowPassFactor;
+    y += (acos(ry / divider) * RADIANS_TO_DEGREES - 90 - y) * lowPassFactor;
+    z += (acos(rz / divider) * RADIANS_TO_DEGREES - 90 - z) * lowPassFactor;
+
+    // The orientations of the accelerometers are different between
+    // Symbian and Maemo devices so we use the different axes
+    // depending on the platform.
+#if defined(Q_OS_SYMBIAN)
+    emit rotationChanged(-y);
+#else
+    emit rotationChanged(x);
+#endif
+
+    // Don't store the reading in the sensor.
+    return false;
+}
+//! [0]