We basically provide a packaged django app that users can install on their devices and use it locally. You mentioned the use of the IP 127.0.0.1, it would work but if they accessed the app from another device in the network it wouldnt let them in.
Is there some particular reason why the app is installed locally rather than being hosted by some service provider?
Its for the users that want to host it on their own devices and only use the app locally.
Is there a way to assign an app id or a specific variable we can implement in our app other than a callback url?