Oxford Dictionary of English for iphone from Enfour Inc.
This new version of the Oxford Dictionary of English, published by Oxford University Press, is a comprehensive online dictionary with word definitions, synonyms, antonyms, spelling suggestions, audio pronunciations, and a user-friendly search interface. Search for words anywhere, anytime, in any language, and with just one tap you can call up the dictionary. The new OED also includes several important additions:
New dictionary - over 10 million words.
Audio pronunciation support - listen to audio pronunciations of the letters of the word and hear the difference between the two sounds.
Listen to the pronunciation and see the corresponding synonyms and antonyms.