Emulated internal storage

I'm going to develop some applications for a smartwatch that runs a Android Kitkat-based operating system, and I'm trying to figure out a way to connect it to the PC to exchange data. Since the internal storage of my Nexus 4 can be accessed simply by navigating the emulated internal SD card, I was wondering if this is an exclusive feature of a specific category of Android devices (such as telephones) or it can be assumed to be present in any device running Android 4+.

Thank you.