Authorizing Custom Web App Builder App and Generate Client ID

[joerodmey]

Trying to authorize my custom app (sitting on my web server) to allow the user to login once and be remembered. I've played around a bit with creating an application and app ID in AGOL. So far I've  created an app ID but seem to be having problems in properly pointing it to my app and passing through the credentials.

Any suggestions on getting to the AGOL login not the ugly login seen below: