Allow users of my app to connect their FreshBooks account

I’ve been running my app as a single user. I have a Zapier/FreshBooks connection that works great. Essentially the app sends some info to FreshBooks which creates an invoice to a customer.

I am now updating my app so that other users like me can create an account.

Is it possible in Knack to allow each user to each connect to their own FreshBooks account? Using just my one FreshBooks account won’t work for this.