The focus in recent years has been on biosensors that allow for the monitoring, prevention, and treatment of health in real-time.  With the rise in popularity of smart wearable devices comes the ability to detect diseases. Soon, a new trend will emerge: individuals improving their health through wearable devices, going beyond just exercising.  The wearable technology industry is booming, and its applications have expanded beyond simple step tracking to include the detection and treatment of medical conditions and the promotion of overall wellness.  Accurately tracking persons is the goal of Internet of Things (IoT) healthcare monitoring systems, which link a variety of devices and services over the Internet to gather, exchange, monitor, store, and analyse data.  In smart applications such as cities, housing, and healthcare, this paradigm allows for the remote control of physical items.  Through the integration of sensor networks into medical care, patient monitoring and diagnosis are made easier, and data may be accessed anytime, anywhere in the world.  Recent health crises have brought into sharp focus the requirement of continuous surveillance beyond traditional healthcare models, since the prevalence of chronic illnesses is an important public health concern.  Wearable computing power is increasing, which opens the door to the possibility of using several full ML-trained classifiers on a single wrist-worn device.  It is now feasible to obtain high-quality biosignals thanks to the proliferation of high-quality biosensors, the majority of which are less invasive wearables.  By integrating this technology with a more thorough comprehension of the environmental elements that precipitate mental health problems, we can improve our ability to detect and respond to potential mental health crises.  Taking care of oneself should be as easy as checking the time on your wrist.  Researchers are actively exploring the potential of consumer wearables to monitor PA, and new innovations in this area are expected to keep popping up in the years to come.