Bluetooth support has been added to KatanaMan and GT1Man/GT1BassMan. This enables connection to the Boss device without requiring a USB connection to your phone/tablet. The connection relies on the use of a compatible MIDI/USB adapter.
At this time, the only validated MIDI/USB adapters are the CME WIDI Uhost (using USB firmware version 3.6) and the XSONIC AirStep Kat (Katana only).
Details on how to set up a Bluetooth connection can be found here : How to use Bluetooth to connect to Boss Katana or GT devices