Alternative forms

What I'm trying to achieve is a form that "outsiders" can fill in to create a new record on the database/table. I need them to see only the fields they need to complete. I also want those fields to appear together on a form (the fields I want them to fill in are distributed across a number of tabs on the main form and would be difficult to find). If Ninox doesn't allow creation of alternative forms for different user groups, is there a way to mimic the effect using subtables or something? 

Thanks, Birger. I understand the "visible if" option. But I have a total of 50 fields on the standard form, on 6 different tabs. Since the fields I want to make visible for outside contributers aren't all be on the same tab, I'm wondering if there's another way to present the fields to the "outside" user group so they all appear in one place. Is there any lever I can pull to make that happen? 

Aaaah .... very good. Thanks!

A couple more questions on this!

(1) I can't find the "create new role" function anywhere. It doesn't appear on the list when I try to invite a new user to a table. Am I doing something wrong, or has the Ninox format changed?

(2) I'm trying to create a role that anyone can use if they have the correct login - a role that functions, in effect, as a webform to collect data. But the user function seems to be specific to individuals and require that individual's email address. So does Ninox allow me to do what I want to do? If so, how?  

Still love the program. Thanks!

Hi, still need help on last two questions. Can anyone shed light...? Thanks!