This paper presents a unique combination of magnetic and inertial sensors on a fully monolithic CMOS chip. Pitch and roll are measured using two identical heat transfer based tilt sensors while yaw is derived from an original electromechanical compass. For complete 3-D positioning, the use of an additional z-axis piezoresistive accelerometer is also investigated. Contrary to systems based on gyroscopes, the proposed device outputs the absolute values of the three Euler's angles. All sensors (i.e. the magnetometers, the thermal tilt sensors, and the z-axis accelerometer) are fabricated simultaneously using a cheap one-step auto-aligned post process (Front Side Bulk Micromachining), thus addressing consumer markets for very low-cost applications.