In this chapter, we study some research issues from IoT-based crowdsourcing in a strategic setting. We have considered the scenario in IoT-based crowdsourcing, where there are multiple task requesters and multiple IoT devices as task executors. Each task requester has multiple tasks, with the tasks having start and finish times. Based on the start and finish times, the tasks are to be distributed into different slots. On the other hand, in each slot, each IoT device requests for the set of tasks that it wants to execute along with the valuation that it will charge in exchange for its service. Both the requested set of tasks and the valuations are private informations. Given such scenario, the objective is to allocate the subset of IoT devices to the tasks in a non-conflicting manner with the objective of maximizing the social welfare. For the purpose of determining the unknown quality of the IoT devices we have utilized the concept of peer grading. Therefore, we have designed a truthful mechanism for the problem under investigation that also allows us to have the true information about the quality of the IoT devices.