  The significant increase in the number of individuals with chronic ailments
(including the elderly and disabled) has dictated an urgent need for an
innovative model for healthcare systems. The evolved model will be more
personalized and less reliant on traditional brick-and-mortar healthcare
institutions such as hospitals, nursing homes, and long-term healthcare
centers. The smart healthcare system is a topic of recently growing interest
and has become increasingly required due to major developments in modern
technologies, especially in artificial intelligence (AI) and machine learning
(ML). This paper is aimed to discuss the current state-of-the-art smart
healthcare systems highlighting major areas like wearable and smartphone
devices for health monitoring, machine learning for disease diagnosis, and the
assistive frameworks, including social robots developed for the ambient
assisted living environment. Additionally, the paper demonstrates software
integration architectures that are very significant to create smart healthcare
systems, integrating seamlessly the benefit of data analytics and other tools
of AI. The explained developed systems focus on several facets: the
contribution of each developed framework, the detailed working procedure, the
performance as outcomes, and the comparative merits and limitations. The
current research challenges with potential future directions are addressed to
highlight the drawbacks of existing systems and the possible methods to
introduce novel frameworks, respectively. This review aims at providing
comprehensive insights into the recent developments of smart healthcare systems
to equip experts to contribute to the field.
