speech to text is not working

i m searching for a long time but i m unable to find API for speech-to-text in iphone. even i got开发者_StackOverflow中文版 some thing in NSSpeechRecognizer but it's framework appkit.framework is not available in xcode but it is in mac os. so i m unable to use NSSpeechRecognizer class what is the problem i m not getting...

if some body has plz tell about that API who can convert speech to text......

I have not tried this, but check Vocal Kit by Brian King. Read more here. It is created with Carnegie Mellon University's (CMU) Sphinx project.