According to a new report, a server-side roll-out looks to have started that enables audio-only mode for the users on Android. The feature is not coming to any specific section or genre streaming inside the Netflix Android app, instead, it is a mode that can be turned on for any video you are watching.
Netflix adds an audio-only mode to its Android app
The Settings menu also shows an Audio Only option that lets you choose when this feature should be enabled. There are three options, ‘Always On’, ‘Headphones or External Speakers’, and ‘Off.’
This appears to be a server-side rollout only as not everyone on Android with the latest app version installed is able to enable this feature.