Automatic Printer Switcher lets you assign a default printer for each application. For example if you want to print images as pdf using tools like NitroPDF or when you print from Word Document you want to use your Office Network printer. This is extremely handy when you have multiple printers attached to your computer and need them changed with the type of work you want to print.
One you install the application, select the program for the list ( it only displays the running program ) and then map it to any of the installed printer. You can always remove or change the default printer as you want.