I was using mybb and they had this option to add a custom field to the inscription process and option to display it on their profile page
e.g : a question What games do you play? + checkboxes to choose from.
I would need some more custom fields to enter data into depending on the category.
So for example I have a "music post" category and want a field "link to audio:"
where the user has to enter a value (mustfield).
I can pay also for it if this is needed!