many orders of magnitude higher than those at the transmitter end. Third, low-level timestamp- ing on such multifunctional receiver devices can be performed to a certain limit and is subject to system restrictions of the underlying firmware. Therefore, motivated by the need to overcome the above limitations but be able to establish a com- mon time reference across resourced constrained BLE devices operating in the ADV_NONCONN_ IND mode, we propose CheepSync.