The Blockstream Jade requires some type of connection to a PC when you first set it up to install its firmware. You can install the firmware either via the Blockstream Green software wallet or from Blockstream's download portal. There is a third (advanced) option that I have forgotten about. You can connect the device either via USB cable or Bluetooth to install the firmware. The same is true for firmware updates, with one difference being that you can install a firmware with disabled Bluetooth. If you do that, then you can only install new firmware updates by connecting the device via a cable.