I use Deezer via my smartphone, usually when i jog or ride my bike. I like it when it suggests songs that I’ve never heard before. At that moment I would like to hit my favourite button the easiest way possible, and add that song to my favourite list of songs.
Instead of unlocking my phone, maybe running through the active apps, finding Deezer, hiting the favourite button and than locking it again, all that while I’m running or riding my bike, it would be great if the favourite button is shown on the locked phone where I have shortcuts for next/previous song and play/pause.
Just sayin..