If you wish to put a pretty GUI onto some command line apps one thing to look at, since most of them are GPL'd, is getting the source and building a full-fledged GUI app with some of the code for the CLI app at it's core. If the CLI app is written in C then it isn't too hard to do since Objective C is 100% compatible with C. The only catch is that you must release the code that you write. (Because of the GPL.)