The support for synced lyrics within the app is impressive. My friend recently demonstrated a feature from her music app that stunned me as to why other apps don't have the same feature.QQ Music (Chinese only) has this feature where the lyrics that the app automatically fetched online (like Deezer) would show up line by line on the car's infotainment screen. Note: this wasn't Android Auto or CarPlay; it was straight out of Bluetooth data received by the car's Bluetooth. I acknowledge that this may be a distraction to drivers alike, but Tesla also has a karaoke or "(caraoke)" feature that anyone can use while the vehicle is in motion.
Here is a Google Drive link to a video that shows what I'm talking about
I'm yet to find any other app that supports this feature and If Deezer does implement this, then I'd be over the moon, honestly.