Is there a way I can have more than one experience and domain assigned to an application ?
You can have more than one domain or slug pointing to an application experience, but at the moment you can only have one experience within an application.
would the URL follow the domain used to get to the experience, or will it switch over to a “main” domain name when accessing other pages within the experience?
Losant does not currently have the concept of a “main” or “primary” domain for an experience - a user accessing an experience will stay on the specific domain they are accessing unless there are links or redirects to the other domains. Right now, if you wanted users to be redirected to a specific “main” domain at all times, you would have to add that logic to your workflows.