The following steps are only needed if running via command line. They are not needed if you are building via Android Studio.
./gradlew assembleDebug
```
Ensure that ADB recognizes your device with `$ adb devices`.
If a single device exists, install via `$ adb install /path/to/apk.apk`.
Assuming you used Gradle like earlier, the file will be called `module_name-debug.apk` in `project_name/module_name/build/outputs/apk/`.
Alternatively, you can simply run `$ ./gradlew installDebug` (`> gradlew installDebug` on Windows) to build, deploy, and debug all in a single command.