How to assign permissions to the standard user for modifying the app properties???

So basically I have three apps I am working upon, these three are facilitator, trainer, trainee apps, so I am supposed to create the apps in such a way that without actually creating the facilitator, trainer, trainee objects for creating records I need to achieve it using user object (or custom user object for that matter). So how can i achieve that?? 

Thanks and Regards 

Hikki