Add-on allows you to hide custom fields from everyone except users of selected JIRA-groups. 

Please notice that fields are hidden by JavaScript so the fields will be visible in page code and they can appear for a second during page loading. The feature might be used to remove some unnecessary fields from screens.

After add-on is installed press 'Configure' button:

In configuration menu select project, fields to be hidden and groups which have permission to see selected fields on screens.