However, an iOS device is also the property of its owner and the owner should be allowed (morally) to install software outside the app store. Even if that comes

However, an iOS device is also the property of its owner and the owner should be allowed (morally) to install software outside the app store. Even if that comes with potential security problems. This is supportable by well known technologies. The user could opt-in to various app-signature blacklists and whitelists. App stores and hardware vendors could publish their official app blacklists and whitelists, and even require their use for warranty purposes. On the other hand, the user could also opt-out.