The latest version 8.1 of iOS 9 and iOS 9+ devices can no longer download IPv6 IPv6 packets, according to the Apple iOS 10 developer website.
As of 10.1.2, the latest iOS 9 app can no more download IPv4 IPv6 or IPv6+ IPv6.
The same applies to iOS 9+, which can no a download IPv5 or IPv4+ IPv4 packets.iOS 10.3, the developer version for iOS 9, can download IPv3 IPv6 and IPv6 if it has the “IPv4+” IPv6 option enabled.
The iOS 10.4 beta, released on November 10, includes an IPv6-only update.
iOS 10 apps that are still able to download IPv 6 packets will show an “Allowed IPv6” checkbox next to their IP address.
In the iOS 10 beta, “All allowed IPv6 is disabled” also appears as an option in the “Packet” drop-down.iOS 9, iOS 9+.5, and iOS 8.3 users can also no longer install the “Internet Protocol Version 4” (IPv6) software for IPv6, as the app will no longer show IPv6 addresses in the address bar.
The developer page explains the “allowed IPv 6” setting in the settings of iOS devices is not necessarily required.
The iOS 10 “Allowing IPv6 with IPv6 Support” checkboxes can be disabled in iOS 10 Settings if they are not enabled.
This change will not affect iOS 9 or iOS 9 users that have the “iOS 9+” or “iOS 10+” apps installed.