For iOS development you can use iSpeech Recognition, OpenEars, Nuance or CMU Sphinx for speech to text. We use iSpeech and it was really simple to integrate.
This means that Leova provides a layer of error correction over and above specifically iSpeech's transcriptions. And with frequent usage (days, not weeks) you'll see Leova's interpretations of buggy iSpeech transcriptions really blow competing NLP parsers' resilience out of the water
To help speed up your ios dev, we've also posted all the libraries you'd need on GitHub and on the first page of the Leova admin console, once you've signed in