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The new iPhone 3GS has support for voice commands, stuff like "call Bill" or "play music by the strokes" and whatnot.
I was looking through the iPhone SDK, but I cannot find any references to this capability. All of the search keywords I choose seem to only find the new voice chat functionality.
Does anyone know whether Apple has added voice command APIs to the SDK, or whether it's yet another forbidden API? If it does exist, could someone point a particular class out to me?
The SDK does not support either voice recognition or text to speech. Voice recognition is only available through the Voice control app, and text to speech is only available through the accessibility APIs when accessibility is turned on.
OpenEars is a really nice Objective-C API for CMU Sphinx. Worth checking out if you want to incorporate CMU Sphinx in your app.
One could try to bundle poketsphinx speech recognition library from the CMU Sphinx project. It is a open source large vocabulary, speaker-independent continuous speech recognition engine. Chech the README to see how to set up in XCode.
来源：https://stackoverflow.com/questions/1121548/iphone-speech-recognition-api