The most interesting part of the Moto Z is its rear. This is where all the modular magic happens. On its own, the phone is pretty thin with a protruding disc nebuild out your smartphone" concept is fun and, importantly, its MotoMods are creative and well-designed. There’s everything from a predictable(but essential) battery back, to a more wild pico projector. Shining your phone onto a wall is an awesome novelty and it’s completely hot swappable.ar the top that houses the camera lens and dual-LED flash.