SQL Server App_name() function - find out which application has modified your data

Sometimes back, my friend told me that they had an application where users update their timesheets. He suspected that some users who had access to the database directly update some entries. He wanted to know whether some users update entries using a query analyser and not using the application. You can use a profiler for this. Another method is to use app_name() function. App_name() function is