Android : What's the best practice for sharing classes between a Wear and Android app?

I'm using a class that I serialize in my Android Phone app, and deserialize in my Android Wear app. They are both in the same Android Studio Project, and are deployed as one.

How can I share the class between the two without having a copy of the class in each package? Right now I'm copy/pasting it, but is there any way for me to include it in both apps?

The directory structure being:

./
    mobile/
           ...src/etc
    wear/
           ...src/etc

How do I handle common classes?