Hi Abhishek.Subramanya & acalbazana,
It is mentioned in the API Developer Portal User Guide that they...
... are used to capture additional information about developers' organizations and applications in the registration and application forms. When enabled, custom fields appear on the form's Additional Info tab.
I am not aware of a way to expose them beyond the CMS. I believe these values are local to the API Portal and not synchronized back to the API Gateway, thus they would not be accessible from the Policy Manager.
The use for the custom fields would be simply for tracking additional information. For example, perhaps you want to know the Country that a user is registering from, you could add a "Country" custom field, etc.
I hope the above helps clarify its use and answers any questions around if it is exposed to the Policy Manager. Please let me know if I can help clarify anything further.
Sincerely,
Dustin Dauncey
Support Engineer, CA Technologies
Email: API-Support@ca.com
Phone: +1 800 225 5224
Outside of North America - http://www.ca.com/us/worldwide.aspx