“…Activities such as walking, walking on stairs, jogging, jumping, driving a motorcycle, driving a car or holding a mobile in hand and placing the mobile on table are known as simple activities. Commonly used sensors in mobile phones are accelerometer [25,26], gyroscope [27], magnetometer [28,29], proximity sensor, light sensor [30], barometer [31,32], thermometer, air humidity sensor [33,34], etc. The user activity can be recognized with the help of these sensors.…”