Spatial crowdsourcing: current state and future directions

Crowdsourcing relies on the contributions of a large number of workers to accomplish spatial tasks, and it has drawn more attention in recent years. Many crowdsourcing tasks are completed online due to its convenience and efficiency. However, sometimes this traditional method may not work due to special requirements involving actual physical locations. Thus, a new paradigm of data collection, called spatial crowdsourcing, has emerged in the past few years. Spatial crowdsourcing consists of location-specific tasks that require people to physically be at specific locations to complete them. In this article we discuss unique challenges of spatial crowdsourcing, provide a comprehensive view of this new paradigm by introducing the taxonomy, and give future directions.