For a read-only view of your cards in any calendar app, yyou can use the Trello Calendar power-up (though you need to be using the browser version of the site, not the Android app to enable it). It exports an iCalenda URL you can easily add to Google Calendar (from the Google calendar site, not from within Business Calendar. From that point on, it just looks like any other read-only calendar in your Google account, visible in Business Calendar.
Deeper integration is a very good idea, but maybe this gets you part way there?
For a read-only view of your cards in any calendar app, yyou can use the Trello Calendar power-up (though you need to be using the browser version of the site, not the Android app to enable it). It exports an iCalenda URL you can easily add to Google Calendar (from the Google calendar site, not from within Business Calendar. From that point on, it just looks like any other read-only calendar in your Google account, visible in Business Calendar.
Deeper integration is a very good idea, but maybe this gets you part way there?