Medical device and secure control system (1) comprising a wearable medical device (2) and a portable medical device controller (4) for control of the medical device. The medical device (2) comprises a control system comprising a communications module including at least short range wireless communications capability. The medical device controller (4) comprises a communications module (17) including at least a short range wireless communications capability for communication with the medical device (2) and a consumer electronic device (12) including any one or more of a smartphone, a personal computer, and a computer tablet. The medical device controller (4) further comprises a memory (14) storing a computer program and encryption keys configured to establish an encrypted communication with the medical device (2) and with the consumer electronics device, and a processor (15) configured to execute the computer program. The medical device controller (4), the consumer electronic device (12) and the medical device store each at least one journal (16) for exchange of journal entries between the medical device controller (4) and the consumer electronic device and between the medical device controller (4) and the medical device (2).
