Why can’t we turn the sound off?! – Quadris - new brick puzzle Review

I love playing this game on Android and iOS but why can’t we have the option to turn off the sound?! I like to play this while listening to Spotify but the dual sounds is distracting and if I have to pick between playing Quadris and listening to Spotify which I’ve been paying for since 2012, I’m picking Spotify. Update with the ability to turn off the sounds and I’ll add that fifth star.
Review by Music (but not yours) lover on Quadris - new brick puzzle.