Supporting IPv6-only Networks

At WWDC 2015 we announced the transition to IPv6-only network services in iOS 9. Starting June 1, 2016 all apps submitted to the App Store must support IPv6-only networking. Most apps will not require any changes because IPv6 is already supported by NSURLSession and CFNetwork APIs.If your app uses IPv4-specific APIs or hard-coded IP addresses, you will need to make some changes. Learn how to ensure compatibility by reading Supporting IPv6 DNS64/NAT64 Networks and watch Your App and Next Generation Networks.

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