  With the advent of seamless connection of human, machine, and smart things,
there is an emerging trend to leverage the power of crowds (e.g., citizens,
mobile devices, and smart things) to monitor what is happening in a city,
understand how the city is evolving, and further take actions to enable better
quality of life, which is referred to as Crowd-Powered Smart City (CPSC). In
this article, we provide a literature review for CPSC and identify future
research opportunities. Specifically, we first define the concepts with typical
CPSC applications. Then, we present the main characteristics of CPSC and
further highlight the research issues. In the end, we point out existing
limitations which can inform and guide future research directions.
