Occasionally, Netflix changes backend DRM keys that render older video decoders permanently incompatible. If streams throw a specific playback error after logging in, the device may only function as a browsing interface rather than a playback tool.

Downloading older versions of Netflix - Apple Support Community

: This is subjective and implies the searcher is looking for the most efficient, functional, or highest quality version or method of obtaining and using Netflix on an iOS device, specifically with the IPA file for version 511.

: A dedicated community focused entirely on keeping legacy iOS 3, 4, 5, and 6 devices alive with functional software. How to Install the IPA via Sideloading

the current Netflix app to register it in your purchase history. On your iOS 5.1.1 device , open the App Store. Go to Purchased or Purchased Apps . Find Netflix and click the cloud download icon.

Because the standard App Store search often blocks downloads for outdated software, you must use a "purchased history" workaround: Apple Support Community