On the secondgeneration Apple TV or older, the channel will no longer be accessible, and on the iPhone, iPad, and iPod touch, iOS 7 or later is required for the app The app on the 3rdgen device is functional, but it is missing some important things, like an indicator on the list of subscribed channels indicating which have new content and which do not You need to actually view each channel's contents in order to determine if it has something new for the thirdgeneration Apple TV is now no longer available, with users only available to view content via AirPlay As announced last month, has dropped support for the thirdgeneration Apple TV, however, the fourthgeneration Apple TV and the Apple TV 4K remain unaffected From that report
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