Accelerometer
It is one of the most basic sensors incorporated in modern smart devices. With any inertial motion in 3 axes, the tiny polysilicon semiconductors slightly bend to give different capacitance, from which the acceleration of the device is determined.
Magnetometer
Similar to a traditional search coil used in physics laboratory, the magnetometer encompasses tiny "search coils" in 3 axes within which current would be induced when perpendicular magnetic field passes through it. The device converts the readings into magnetic field strength.
Gyroscope
The working principle of gyroscope is similar to that of accelerometer except that gyroscope detects rotational motion rather than translational motion.
Light Sensor
The light sensor relies on the famous photoelectric effect from Albert Einstein where photocurrent is generated across photocell upon receiving light. The photocurrent is then converted into corresponding light intensity.
