I want to invite someone as team member to the iOS developer program. Is it possible to restrict his rights to only one app? He should be able to create/edit/delete certificates for app 1A but not for app 2B.
You can set which user has access to which apps in iTunes Connect (Appe Support Article)
From the homepage, click Users and Roles, then click iTunes Connect Users. Click the Apple ID for the user you want to edit, then click Roles. In the Apps section, choose an option from the pop-up menu: