add a field at first registration

Amit,
JFBConnect doesn't store any user profile information directly. However, we do integrate with multiple other extensions with profile systems that you can pull Facebook profile information into. Currently, we support JomSocial, Community Builder, Kunena, K2, Agora, and Virtuemart.

Hope that helps, but if you have any questions, just let us know!

Thanks,
Alex

Amit,
If you're using any of the extensions I mentioned above, you can have extra fields that aren't mapped displayed during the registration process. In the Profiles section of JFBConnect, there is an option for Show Fields At Registration which you just need to configure. If you're using one of those extensions, and you need help configuring it, just let us know what one you're using and we can help further.

Additionally, Joomla ships with a "User - Profile" plugin which you can enable and will show additional fields during registration both with Joomla and JFBConnect.

Hope that helps get you started,
Alex