Smart and sustainable cities aim to enhance urban living by integrating technological and sustainable practices. However, several gaps have hindered their full realization. First, integrating diverse technologies and developing a robust infrastructure pose considerable challenges, requiring comprehensive strategies for seamless operation across various urban systems. Data privacy and security have emerged as critical concerns, requiring protecting citizens’ information against breaches and misuse. Digital divide and inequality represent another gap, as not all populations have equal access to digital resources, exacerbating social and economic disparities. These initiatives’ funding and financial models often lack the innovative mechanisms necessary to support long-term sustainability. Governance and policy frameworks must evolve to guide the development and implementation of smart city projects and ensure they meet all stakeholders’ needs. Public engagement and acceptance are crucial to the success of smart initiatives, necessitating strategies that foster community involvement and buy-in. Interoperability and standards are essential for the compatibility of technologies and systems; however, the absence of universal standards complicates integration efforts. While aiming for sustainability, the environmental impact of smart cities must be carefully managed to avoid adverse effects. Skill gaps and the need for workforce development present challenges in maintaining and advancing smart city technologies. Finally, effective monitoring and evaluation mechanisms are required to assess progress, adapt strategies, and ensure the achievement of smart and sustainable objectives. Addressing these gaps is vital for fostering the success of smart and sustainable cities.