Create a role (besides view, edit, and own) for users, which will allow for switching between staging/production environments, but will hide the 'edit app' button.
I am aware that I can modify which resources are available for each user group, but currently there is only 'view' 'edit' and 'own'. I would like 'QA' to be added to this list, so the staging/production dropdown is available for our QA team. However we do not want to give them access to edit the UI or the tool.