Thanks for upgrading to a paid account!
With the account you have right now, you can only have one web app; the custom domain you have set up is that one. If you upgrade to an account with two web apps ($2/month more for your type of account), then you can fairly easily set things up so that they both have the same contents:
- Create a new web app with the
username.pythonanywhere.com
domain -- just choose the "Manual configuration" option, and the version of Python that your custom domain is currently showing.
- Once that's created (and showing a "hello, world" kind of page), go to your custom domain on the "Web" tab
- Go to the WSGI file for your custom domain (it's linked on the page for that domain)
- Copy all of the contents.
- Go back to the Web tab, and select your
username.pythonanywhere.com
domain.
- Go to its WSGI file
- Paste the stuff you got from the custom domain's one, completely replacing the existing contents, then save.
- Go back to the "Web" tab.
- Make the other settings on that tab (eg. virtualenv and static file settings) on the
username.pythonanywhere.com
domain match the ones on the custom domain's page.
- Reload the
username.pythonanywhere.com
domain
...and you're done. Any code changes you make will be reflected on both domains.