It looks like Netflix is testing a new, redesigned version of its app and making it available to a few users. One user on Reddit received an update while using the stable version of the app and found a completely new user interface.
The new user interface (right) adds a navigation bar to the bottom rather than relying on the slide out menu, saving you a swipe and making the buttons easier to reach on a large phone. The differences in the size of various elements are likely due to DPI settings, as the right screenshot is from a Galaxy S6.
This is likely just a test, but we might see a full rollout of this new version soon. It’s definitely a welcome improvement to the cluttered slide out menu!