In this article, a crowdsourcing scenario with multiple heterogeneous tasks and multiple IoT devices is studied as a two-tiered process. In the first tier, it is assumed that a substantial number of IoT devices are not aware of the hiring process and are made aware by utilizing their social connections. Each IoT device reports a cost (private) and is strategic. For the first tier, a truthful budget feasible mechanism is proposed. In the second tier, a set of quality IoT devices is determined and each of them reports private valuation that satisfies gross substitute criteria along with its favorite bundle of tasks. The truthful mechanisms are designed independently for determining the quality of IoT devices, and for hiring them and deciding their payment. Theoretical analysis shows that the proposed mechanisms are computationally efficient, truthful, correct, and budget feasible. The simulation is done to compare the proposed mechanisms with the existing mechanisms.