Balance Custody currently supports both US Dollars (USD) and Canadian Dollars (CAD) when displaying the fiat value of digital assets. 

The fiat value recorded using the fair market value of the digital assets at the time a transaction is generated. To switch between seeing this value in USD and CAD, click on your name at the top right corner and select "Switch to USD" or "Switch to CAD" to begin seeing fiat values in that chosen currency (even after logging out and back in) as well as in the Signing Tool.

To switch back, simply navigate back to this menu and select to switch the currencies again.