Limitation of existing work 8 Strong assumptions: instantaneous constraint Batch manner: fixed batch and lacking in global theoretical guarantee Y Tong et al, Online mobile microtask allocation in spatial crowdsourcing In ICDE 2016 Y. Tong et al, Flexible dynamic task assignment in real-time spatial data In VLDB 2017. P Cheng et al, An experimentalevaluation of task assignment in spatial crowdsourcing. In VLDB 2018 L. Kazemiet al Geocrowd: enabling query answering with spatial crowdsourcing In GIS 2012 L. Kazemiet al Geo TruCrowd: trustworthy query answering with spatial crowdsourcing In GIS 2013.Limitation of existing work 8 ⚫ Strong assumptions: instantaneous constraint ⚫ Batch manner: fixed batch and lacking in global theoretical guarantee Y. Tong et al, Online mobile microtask allocation in spatial crowdsourcing. In ICDE 2016. Y. Tong et al, Flexible dynamic task assignment in real-time spatial data. In VLDB 2017. L. Kazemi et al. Geocrowd: enabling query answering with spatial crowdsourcing. In GIS 2012. L. Kazemi et al. GeoTruCrowd: trustworthy query answering with spatial crowdsourcing. In GIS 2013. P. Cheng et al, An experimental evaluation of task assignment in spatial crowdsourcing. In VLDB 2018