With so many customized playlists that suggest music for the listener (music Spotify's algorithms identify as music the listener will like), it only makes sense the user will want to add many of these songs to their library by liking them. This process should be made as easy as possible for the user by letting them do so from the lock screen. A Spotify listener should not have to unlock their phone every time they want to like a new song. It is inconvenient and even dangerous in instances where the user is driving or performing another activity.
Updated on 2019-11-28
A similar idea has also been suggested here:
Please vote for it, and add a comment there, so it may be considered. Any update on the matter should be posted there.
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