It is opt-in on iOS for Applications. Applications have to declare upfront what sites they will communicate with. It is called app transport security. if you d

It is opt-in on iOS for Applications. Applications have to declare upfront what sites they will communicate with. It is called app transport security. if you don't set it up your app boots in a sandbox with no network. Settings -> Privacy Security -> App Privacy Report Unfortunately 1 - as a _user_ you cannot opt-in or out. I wish Apple would take the next step and let us select which sites an app is not allowed to communicate with. Or ideally even globally for all apps. Unfortunately 2 - the list of sites the app wants to communicate with is not clearly communicated upfront like before you install. Unfortunately 3 - the list can also contain wildcard domains Small steps - they really need to push this to the next phase IMO.