Placing your phone on one of the three unmarked positions starts one of the three actions (Play, Pause and Radio). These positions are only visible when powering-up the device and briefly as the action initiates. The reasoning behind not having any marks is that when an interface is this simple and is used by the same people all the time markings outlive their use very quickly and become nothing more than visual clutter.
Inspiration for the object and how it is positioned in the home came from the “key-bowl” – a place where you put your keys when you come home since you have no use for them within the home. Now this isn’t really true when it comes to your phone but with more and more devices that compete for your attention together with the fact that phones are getting larger and larger many people do unload their phone somewhere when they get home.