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.
So that's where Leova really shines. We saw this shortfall in accuracy when we were using iSpeech for testing on iOS, so we built a machine learning system that generated structured phonetic dictionaries.
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
if you're curious to try this out - I'd recommend you sign up (free), download the IPA file (also for free) and try it out (also free!).
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