Yep that's true. I test it on Samsung s10e USB c to micro b. Record wideo and sound in good quality. There is no need any additional app

Just in case someone finds this post in the future: yes it works. 

Bought a USB micro to USB C cable and works perfectly.

Hi, is the OTG support important for USB adapter to work with type c phone?

I just upgraded my mobile phone and it has an USB type C port. 

I know this is not officially supported by Roland, but I'm wondering if anyone has tried to use a Type B to Type C cable to connect to the mixer. 

I believe it should work, but would like to check before adding yet another cable to my collection. 😁

FWIW, the phone is a Google Pixel 4a. It supports OTG so software wise it should work. 

Thanks!

Using a Roland GO:Mixer with a phone that has USB-C port