  A substantial amount of growth is being achieved by businesses through
IoT-based services. The emergent of small electronic devices capable of
computing, which are commonly known as wearables in IoT domain has proven to
have huge impact in people's life. Theses wearables are capable of collecting
vital information about a person's activities and behaviours regularly. This
makes them suitable for many applications in health monitoring, fitness,
sports, education and some industry related applications. To this end, in this
paper, we aim to provide a general review on IoT-based wearables, the sensors
adopted for several categorized wearables, the communication technologies
adopted and the most widely adopted data processing techniques for wearables.
Furthermore, we present the challenges faced for wide adoption of wearables and
the future research directions.
