Goal: Reduce dev - feedback cycle by using App Engine dev server. For my use this must be available as a public HTTPS address. App Engine dev server only supports HTTP.
ngrok supports https urls to any http port, so you can just use ngrok to proxy an https domain to the GAE dev server port
If you have a paid for account, you can setup CNAMEs to use your own domains
ngrok http -hostname=dev.example.com 8080