Table 4.

Different wireless sensors used in mHealth.

Sensors	Functions
ECG (Electrocardiograph)	Monitors heart activity, cardiac arrhythmias, heart failure [104]
EMG (Electromyography)	Monitors muscle activity [105] & Ergonomics [106]
EEG (Electroencephalography)	Monitors brain electrical activity [107] & Stress recognition [108]
PPG (Photoplethysmograph)	Monitors pulse and blood oxygen saturation [109] & monitor hypopnea (i.e., sleep condition) [110]
Cuff-based pressure sensor	Monitors blood pressure [111]
Resistive or Piezo Elelctric chest bell sensor	Monitors respiration & Respiratory tract infections [112]
Tilt sensor	Monitoring trunk position [113]
Gyroscope Sensor	Gait-phase detection [114]
Accelerometer	Estimates type and level of users activity [115]
Smart sock/insole sensor	Count steps/fall detection [116]