This looks like an app I've been using to see what my friends are listening to called greymatter.fm. I haven't been able to try out Humit yet as I'm on iOS. Waiting to see what it looks like.
Sweet! Can't wait for more people to start using grey matter more... To answer you question about my preference.. for starters you dont need to have a paid spotify to use grey matter. It seems like with humit you need a spotify account to get into the app. I have a lot of friends that dont have spotify so grey matter is working better right now for us. Also in grey matter you can also search for songs in apple music.... i think they are going to connect to soundcloud and bandcamp sometime this year too which would be REALLY awesome. Hope this helps!