Enterprise App Stores
Because Apple's App Store is for consumers, companies are unable to distribute in-house apps on the App Store. Under Apple's iOS Developer Enterprise Program companies can publish in-house apps using an Enterprise App Store.
Apps published with Apple's iOS Developer Enterprise Program are still subject to Apple's control via the controversial kill switch, where Apple can revoke a publisher's digital certificate and thereby "kill" the app on user devices. However, there is no evidence that this has been done in the enterprise environment.
Read more about this topic: App Store (i OS)