As you can see in the screen shot at right, the demo provides various aspects about the current string including the string in a letter, word, or using a WordBoundary. It works just like CFStringTokenizer can, but can be accessed using this front-end.
If you're wondering what CFStringTokenizer actually is, it's useful for breaking a string into a token, which can specified by words, sentences, or paragraphs. You're also able to further modify the tokenization once you break it down.
This is something that's going to be useful for iPhone developers who like to work with a Cocoa Touch interface to bring lower-level elements of the iPhone OS into their apps, and also to developers who work with natural language strings.
To download this project, go over to the cocoa-stringtokenizer project page on GitHub.