A payment module with one or more processors, memory, a short-range wireless transceiver (e.g., BLE), and a first interface module configured to couple the payment module with a control unit of an offline-payment operated machine that includes a coin receiving switch. The payment module receives a transaction request via the short-range wireless transceiver from a respective mobile device to perform a transaction with the offline-payment operated machine. In accordance with receiving the request, the payment module causes the offline-payment operated machine to perform the requested transaction by issuing one or more electronic pulses emulating one or more signals issued by the coin receiving switch to perform the transaction to the control unit of the offline-payment operated machine via the first interface module.