artifacts.gradle

android.applicationVariants.all { variant->;
    def appName
    //Check if an applicationName property is supplied; if not use the name of the parent project.
    if (project.hasProperty("applicationName")) {
        appName = applicationName
    } else {
        appName = parent.name
    }

    variant.outputs.each { output->;
        output.outputFile = new File(output.outputFile.parent,
                "${appName}-${output.baseName}-${variant.versionName}.apk")
    }
}