users in my site collection can create subsites by self service site creation. There is a Nintex Workflow and Forms for Office 365 added to the tenant (trial version). But users cannot add the apps to their subsites - there is a message that only site collection administrator can grant the access to the application. I as a site collection administrator am able to add the apps to any subsites. What am I missing or what should I do to grant users access to the apps so they can add them to their subsites?
Please, it is urgent.