A wireless mobile device, and a computer-implemented method of distributing encryption keys to Internet of Things (IoT) systems begins with the wireless mobile device requesting IoT systems keys from a key management system with a first radio transceiver. Next, the requested IoT systems keys are received. Each of the IoT systems keys is i) encrypted with a public key from a recipient IoT system, and ii) signed by the key management system. In response to the wireless mobile device being located in proximity to the recipient IoT system, identifiers of the IoT system are received by the wireless mobile device with a second radio transceiver. The wireless mobile device selects at least one of the IoT systems keys that corresponds to the identifiers. The IoT system keys are transmitted from the wireless mobile device to the recipient IoT system with the second radio transceiver.