As reported by Pitchfork, Spotify has patented a new system that monitors user speech to "make recommendations." The company applied for the patent in 2018 and it was granted on January 12, 2021. According to the patent, the software tracks "intonation, stress, rhythm, and the likes of units of speech” from the user’s voice while the cell phone has the app installed (and not necessarily when it is in use). The software is also capable of using speech recognition to identify metadata points such as emotional state, gender, age, accent, and if someone is alone or with other people.
Spotify issued a vague statement to Pitchfork: "Spotify has filed patent applications for hundreds of inventions, and we regularly file new applications. Some of these patents become part of future products, while others don't. Our ambition is to create the best audio experience out there, but we don't have any news to share at this time." The software does not appear to be implemented… yet.