Technically it’s possible through the browser as long as you have a way to cache the javascript files. The reason to use app when the controller is in AP mode is that due to lack of Internet connection, the javascript files need to be accessible locally — the app embeds these so it will work fine. But there are also ways to cache them in a browser so you can use a standard browser as well.
We used to support browser apps (like Chrome apps) in the past, but over time such support has been dropped (for example, in recent news Google is discontinuing Chrome apps)