Page Comparison

This tutorial follows a sample application called Deal Tracking that you can find  here:

The Deal Tracking application has one Form for entering new deal opportunities and a second Form which contains the user experience and logic for querying, viewing and making changes to opportunity records that have been entered.

...

app.showMessage('Success', 'You Updated the Record', 'success');

This function produces a dialog that looks like this:

Image Added

To take this a step further you could tie the app.showMessage function to a 'service listener' which executes the code when the update service has completed. This way it will only show when the service has successfully executed.  An else condition could be added to show an "unsuccessful" message in the event the that the service call failed.

var srv = form.getServiceConfiguration('SC_ServiceConfig1'); //makes sure you set the ID of your Update service        

srv.connectEvent("onCallFinished", function(success)            
{
  if(success) {                                                                                        
    app.showMessage('Success', 'You Updated the Record', 'success'); 
  }
});

...