Google Analytics (SDKBOX) - do I need to setUser?

Services 3rd-Party
#1

Google Analytics plugin:
http://docs.sdkbox.com/en/plugins/googleanalytics/v3-cpp/

Do I need to use this function to identify unique App user? Or it has different purpose?

static void setUser ( const std::string & userID ) ;

If I do not set userID, does this plugin sets some ID for App users automatically?

#2

In general you do not need setUser by yourself.

By default, Analytics assigns each device a unique Client ID, and considers each unique Client ID as a unique user in your reports.