This is one of those obvious things to do with a device like an iPhone  but  this is such a  neat  expression of  extending an iPhone as a control surface by creating a virtual 10 key pad  to go next to  your laptop, your Apple laptop so far. Many of the companies that specialized in home theater have controllers that cost two times that of an iPod touch can  now   use that  same job for providers like mainlobby and sonos.    

There's so many  niche uses for using this as a  remote  surface /  display  that just about anything you can address over ip ( anything if you have the time )   such as  incubators and hatchers  which  still look like heathkit made most of the controls  These things are far more useful  than just making phone calls  which is   sometimes  a possibility on the iPhone.  ( Mine still cuts out, fails to connect, hold calls so it looks like that's a problem that's here to stay )


 

Turn you iPhone into a 10-key number pad | iPhone Buzz