It's okay to question the purpose of this app - what exactly is it for, anyway?
Imagine that you're at the office and you want to take a short break to read the paper, check your mail, or chat with someone on messenger. Just start up this application and relax, because anyone that passes by your computer will think that it's tied up doing something.
It's possible to modify both the window's title bar as well as the message it displays. Just click the icon situated to the left of the bar.
You can even change that icon: there are seven different options to choose from.