For those unaware, Haiku applications have certain information stored in resources. This includes the version, short and long descriptions, and a duplicate of the signature specified in the application object's constructor. You can easily set this information quickly by adding an .rdef file, which is a text-format resource file.
To quickly create and edit this information, add a new file by pressing Alt+N or choosing Add New File from the menu and enter the name of the .rdef file, such as Resources.rdef. Double click the file's entry and when it opens, you will be greeted with a text file where you can fill in the information for your application with a minimum of fuss.
Editing .rdefs not to your liking? Make a Resources.rsrc file instead, right-click on it, and choose "Edit Program Settings" to do the same thing with the FileTypes app. Either way, simple and fast. That's the way we like it. ;-)