I got the answer elsewhere, copying it here in case it is of use to anyone:
We currently only have options to shut down the system through our webinterface. However, the URL command for shutdown can be copied and used as a one-click solution for any device, like smartphones, tablets, etc. The command is:
We have noticed that a few people have requested a function to shut down the device through Jivelite and will try to include this in a coming update. Thanks your feedback.
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