Smart cities have proliferated worldwide in recent years, responding to the efficiency drive of urbanization. However, the approach of Smart City risks deepening the digital-divide problem. While massive technologies are intensively deployed, some potentially disadvantaged groups such as the aged and disabled people are often excluded and left behind due to their limited abilities and opportunities in interacting with others. There is a compelling call for policy measures to enhance the accessibility and inclusion of these disadvantaged groups in smart city development. This study aims at discussing the role of technology in urban development, and more importantly the causes and solutions of digital-divide by reviewing current situations and practices. It firstly introduces the scopes of smart city and the role of technology as an enabler, rather than as the only determinants of smart city development. Then it discusses the phenomenon of digital divide and its root causes. It is found that digital-divide is a complex with multiple layers, and it can be caused by various factors including insufficient facilities/services, individual attitude barriers and the lack of external support. Based on lessons from the practice of enhancing digital inclusion in Singapore and South Korea, this study concludes with the recommendations for narrowing digital-divide to build an inclusive smart city.